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LATE MODEL RULES

Refer to the 2025 NASCAR Rulebook. 

GENERAL: 

ENGINE, TOTAL WT // RIGHT SIDE WT CARBURETOR               

 

GM 604 Crate, 3100 lbs // 1375 lbs                          HOLLEY 650 CFM, 1” open spacer

 

GM “Upgrade”, 3100 lbs // 1375 lbs                          HOLLEY 500 CFM-HP / ULTRA-HP/ ULTRA-XP, 1” tapered spacer

 

GM “Harrington Enforcer”, 3100 lbs // 1375 lbs        HOLLEY 650 CFM, 1” open spacer

 

Ford 347 SR Crate, 3100 lbs // 1375 lbs                   HOLLEY 650 CFM, no spacer

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** Chains or cables on the rear end to stop traveling when jacked up must be installed with bolt and lock nut. No quick release pins will be allowed. When jacking the car up, the frame must jack up a minimum of 2 inches before the tire clears. If not connected on both ends, it must be removed before you race.

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* Must have rocker panels on both sides of the car. The rocker panels must be of matching thickness on both sides with a minimum thickness of .025" thickness, magnetic steel. It will be mandatory by July 1, 2025.

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* Maximum width of body parts and side skirts between the front and rear tires is 77 1/2". The right door and quarter panel must be flat and not concaved in. 

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* The rear window must have a vertical brace in it to keep it from pushing in. The rear and side windows must have all the screws / rivets in and tight. 

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* If any of the body components cannot be fixed, you will add 25 lbs to the right side. 

CHARGER RULES

COMPETING MODELS: 

1970-2023 rear wheel drive cars with a minimum wheelbase of 104” Wheelbase.

CAR BODIES:

  1. Stock or aftermarket LMSC legal steel or composite bodies only. Camaro and Mustang per SELLM Series specs.

  2. All bodies must meet roof and spoiler height template specifications per LMSC rule.

  3. All bodies must be approved by speedway.

  4. All cars must be painted and lettered professionally.

  5. Rocker panels may be fabricated but must maintain 4” ground clearance.

  6. Must have rocker panels on both sides of the car. The rocker panels must be of matching thickness on both sides with a minimum thickness of .025" thickness, magnetic steel. It will be mandatory by July 1, 2025.

  7. Maximum width of body parts and side skirts between the front and rear tires is 77 1/2". The right door and quarter panel must be flat and not concaved in. 

  8. The rear window must have a vertical brace in it to keep it from pushing in. The rear and side windows must have all the screws / rivets in and tight. 

  9. Windshields must be Lexan or Plexiglass may be installed in the rear quarter windows. 

  10. Speedway approved window net must be installed in the driver’s side window opening.

  11. There will be no ride height rule for 2025. Cars are subject to be placed on ride blocks to check templates and other rule specs.

  12. On all approved 2007-2019 models, the rear spoiler must not exceed five (5) inches in height, 54 inches in width, and be centered on the car. The maximum rear spoiler height from the ground to the top of spoiler will be 39".  The spoiler angle must be between 50 - 60 degrees.

  13. On all approved 2020 models, the rear spoiler must not exceed five (5) inches in height, 64-1/2" in width, and be centered on the car. The maximum rear spoiler height from the ground to the top of spoiler will be 39-7/8". The spoiler angle must be between 50-60 degrees.

  14. Wrecker hookup required front and rear of car.

  15. The new Late Model Stock Car body will be allowed for competition in this class.

  16. If any of the body components cannot be fixed, you will add 25 lbs to the right side. 

FRAME:

  1. Stock OEM front sub frame with tubing frame connector allowed.

  2. OEM stock clip must have factory OEM mounting points for weight break. Rear trailing arm mounts may be fabricated.

  3. Frame rails minimum 2”x 3”.

  4. A Steel firewall must separate the driver from the engine compartment and fuel tank.

  5. All body heights are subject to being checked at any time. When checked the car will be placed on the ride blocks if they are too low and all specs must meet requirements. There will be no ride height rule for the frame heights. 

ROLL CAGE:

  1. A complete speedway approved roll cage.

  2. Roll cage must be constructed of roll bar tubing with a minimum outside diameter of one and half 1 ¾” inches x .090 wall thickness.

  3. Roll cage must be centered on the frame. Perimeter style.

  4. Main roll cage uprights must be on top of outside frame rails.

  5. Full cage is required with four uprights and four top bars.

  6. Roll bars may go through front and rear firewalls.

  7. Minimum of four bars in driver’s and passenger’s door required.

  8. All bars within drivers reach must be padded.

  9. Drivers’ door bars must be plated with 1/8” steel LMSC style.

SUSPENSION:

  1. All suspension components must be in compliance with the NASCAR Advance Auto Parts Weekly Series rule book.

  2. OEM type steering box. Aftermarket tie rods, center-link, idler, pitman arm, allowed. No rack and pinion.

  3. No one piece billet spindles allowed.

  4. The front sway bar may be OEM or aftermarket. Mounting points may be aftermarket. The front sway bar must have a maximum of no more than 1.5” size diameter.

  5. Steel rear lower trailing arms required.

  6. Rubber bushing, metal bushing, Teflon bushings or heim joints allowed. Whichever bushing is used, it must be the same on both sides.

REAR END:

  1. Rear-end may be car, truck, or floater. Any ratio. A standard quick change will be allowed.

  2. Detroit Locker, or locked rear end only.

  3. No Cambered Rear End Housings. +/- .4 Grace

  4. Chains or cables on the rear end to stop traveling when jacked up must be installed with bolt and lock nut. No quick release pins will be allowed. When jacking the car up, the frame must jack up a minimum of 2 inches before the tire clears. If not connected on both ends, it must be removed before you race.

SPRINGS and SHOCKS:

  1. For all NASCAR Advance Auto Parts Weekly Series book for specifics on springs allowed.

  2. Bump stops, coil binding, or any travel limited devices will not be permitted.

  3. Only one (1) spring rubber insert will be allowed per spring. The spring rubber must not exceed one (1) full coil and be acceptable by Track Officials. Coil spring wire wrap will not be permitted.

  4. Shocks may be claimed by any Charger driver finishing in the race for $325.00 cash each. Shocks to be claimed must be in writing to officials with cash within 10 minutes after the race. The team performing the claim must finish on the lead lap and can only protest within 5 positions of the finishing order. The car that has their shock(s) being claimed has 10 minutes to make a shock claim to the team filing the original claim from the time it has been presented.

5. SHOCK ABSORBERS (Section A-Z)
A.   Shock absorbers and components must be from an approved manufacturer. The approved shock absorbers will be of the revalvable, rebuildable, gas pressurized, mono-tube, deflective disc valve type with an integral gas reservoir. Shock absorbers must provide a resultant force dependent upon piston velocity and must be acceptable to Track Officials. Shock absorbers and components must be used as supplied by the manufacturer and all components must be used in only their respective manufacturers’ shock absorber. Modifications or changes to the shock absorber and internal components will not be permitted. Shock absorbers and components must be available to all Competitors and must meet the following requirements.  As per local Track Rules, oil type shock absorbers will be permitted. Specifications and rules for these oil type shock absorbers will be developed, implemented, governed, and enforced by the individual Track Rules.  

B.    The approved shock absorbers and components are as follows: 

  • Penske 7500 Series with only the approved Penske Digressive, Linear and High-Flow Pistons  

  • Bilstein ASN, SN or AS2 Series with only the approve Bilstein Linear U37T Series Pistons #423171 and #403556 

  • C2P NAEX Series with only the approved Linear #62070 and Hi-Flow #40094 Pistons 

  • Advanced Racing Suspensions 4000 Series with only the approved #40094 Piston 

  • PRO PG Series with only the approved Linear/Linear #63 Piston

  • JRI ST/08 Series with only the approved #3803-15 Piston 

  • Blackmagic Shocks (Shadow Racing Products) BML Series with only the approved BML Linear Piston 

  • In addition, AFCO and PRO shocks will be legal WITHOUT base valves.

C.      Changes in shock absorber force must not be made by the position of the shock absorber shaft, only by the velocity of the shaft through the compression and rebound stroke.  

D.    Track Officials may use a shock absorber and internal components provided by the respective manufacturer as a guide in determining whether a Competitor’s shock absorber and internal components conforms to the specification of the Rule Book. 

E.     The only shock absorbers and internal components permitted will be those approved by NASCAR and Track Officials.  

NOTE: The internal bore of the shock absorber body must remain as supplied by the manufacturer. The internal bore diameter of the shock absorber body must be the same from top to bottom. Tapers, steps, grooves, and other misalignments will not be permitted. Modifications which provide position sensitive piston travel will not be permitted. 

F.    Shock absorber base valves will not be permitted. 

G.    “Steel” deflective disc valve shims must seal the primary metering faces of the single piston in the main shock body. The only shims permitted will be those manufactured, produced and/or recommended by the specific shock absorber manufacturer. Shims must be used in only their respective shock absorbers. Ring shims and bleed shims will be permitted. Floating shims will not be permitted. The shim stack must be of the single pyramid type with the exception that multiple shims of the same size may be stacked together. The inside diameter of the shims must match the shaft diameter with the exception of the outer ring of the ring shim. 

H.  Only a single one-piece piston is permitted in the main body with one (1) shim stack on the compression side, and one (1) shim stack on the rebound side. A maximum of three (3) bleed holes may be drilled in the piston. If bleed holes are drilled into the piston, they must be drilled into the port of the piston only. The only pistons permitted are the Linear and High-flow pistons that were submitted by the manufacturer and approved by NASCAR. The piston band must be the original band for the approved manufacturers piston. The piston band and piston band groove in the piston must remain the standard size and must not be altered. 

I.  One-piece open style jets that bleed equally in both compression and rebound will be permitted. One-piece jets that control flow in compression only or rebound only will be permitted. Solid plugs in place of open jets will be permitted. Plugs with fixed bleed holes will be permitted. Check ball jets that control flow in compression or rebound only will be permitted. 

J.  The gas reservoir maximum outside diameter must not exceed 2.300 inches. External shock absorber gas reservoirs will not be permitted. 

K.  The single floating divider piston in the integral gas reservoir must be installed to the manufacturer’s specifications without any modifications. 

L.  The gas reservoir must not be filled with any material other than in an inert gas form. Oils or any other types of liquid or materials that are not approved by NASCAR or Track Officials will not be permitted in the gas reservoir side of the shock absorber divider piston.  

M.  The shock absorber nitrogen gas pressure must not be less than 50 psi or greater than 150 psi. Gas pressure will be measured at ambient temperature (not to exceed 100 degrees Fahrenheit) by temperature monitoring devices used by Track Officials. Gas pressure will be checked with the shock absorber removed from the race vehicle and fully extended. AZer being charged, at any time, the shock absorbers must fully compress and fully extend the entire length of the shock absorber shaft with the external adjustment (if used) set in any position without any type of mechanical assistance. An external Schrader valve, needle valve, etc. will be required to pressurize the shock absorber with gas. The competitor must have the equipment required to adapt to the technical inspection equipment to check the gas pressure in the shock absorber. 

N.  Oils that the viscosity can be changed by any type of electro-magne5c field or by any other means will not be permitted. 

O.  Shock absorber shaft diameter must not exceed 0.630 inch and the shaft must not have any sleeves or spacers that could limit the travel of the shaft into or out of the main body. Shock absorber shafts must be solid on all non-adjustable shock absorbers. When single adjustable shock absorbers are used hollow shock absorber shafts will be permitted. 

P.  Suspension travel must not be limited by the shock absorber and/or components, or shock absorber mounting location. 

Q.  Coil over shock absorbers will be permitted. 

R.  Remote or electronically controlled shock absorbers will not be permitted. 

S.  A maximum of one (1) shock absorber per wheel will be permitted. 

T.  Quick disconnect shock absorber mounts will not be permitted. The shock absorber must be attached with positive nut and bolt mounting fasteners. Adjustable shock absorber mounts of any type will not be permitted. Shock absorbers must be mounted on the vehicle with the gas reservoir to the top. Shock absorber eyelets of different lengths will be permitted but must not limit the travel of the chassis. 

U.  Shock absorbers will not be permitted inside of the front or rear coil springs, with the exception of the coil over type springs.  

V.  All rear shock absorbers must be mounted behind the rear axle housing. 

W.  The rear shock absorbers must not angle inboard towards the center of the vehicle more than 30 degrees from vertical. 

X.  Heating pads and/or blankets will not be permitted for warming the shock absorbers.  

Y.  Shock absorbers and internal components are subject to inspection at any time by Track Officials.

Z.  It is the responsibility of the driver, not NASCAR or Track Officials, to ensure the shock absorbers are used in accordance with the manufacturer’s instructions and specifications. 

BRAKES:

  1. Single piston metal brake calipers required. All 4 wheels must work.

  2. Steel disc brakes may be used on front and rear.

  3. Aftermarket brake and clutch pedal allowed.

  4. Dual master cylinder allowed. Any type Brake bias adjusters allowed. 

WHEELBASE and TREADWIDTH:

  1. All vehicles must compete with a wheelbase of 105”. Both sides must be between a minimum of 104 ½” and a maximum of 105 ½”. Any device or procedure which has the ability to dynamically change the wheelbase beyond normal travel parameters will not be permitted.

  2. Vehicles must not exceed the maximum allowable tread width of 64 ½”, front and rear, measured at the center of the tire, zero toe in, at spindle height. Tread width may also be measured at the outside of the left side wheel bead to outside of the right side wheel bead and must not exceed 74 ¾”. A tolerance of ½” will be permitted between the front tread width and rear tread width, but the tread width must not exceed 64 ½”.

CRATE ENGINE chev#88958602, chev#88958603, chev#604, ford#347jr

  1. These Crate engines can be used as all supplied parts from factory manufacturer including gaskets. With or without seal bolts on engine. These engines are subject to teardown procedures and legalities determined by tech committee.

  2. Crate engines are designed to cut the cost of racing. Anyone found tampering with these engines will be fined up to $1000.00 for each offense and loss of points.

  3. Run them as supplied from the factory to ensure legality. Contact Tech Official if you need clarification to this rule.

  4. Aftermarket valve covers are the only part that may be changed on the crate engine.

  5. 602 Crate engines will be allowed to run oil pans off of the GM 603 engine.

  6. 604 Crate engine rules will be directed to the NASCAR rule book.

  7. Ford 347JR Crate engine rules will be teched per Ford specifications. There can be NO changes or modifications made except to Ford factory tolerances.

ENGINE:

  1. Only stock production engines allowed. Chevrolet 350 cubic inch maximum, Ford 351 cubic inch, Chrysler 360 cubic inch plus overbore.

  2. No Chevrolet 400 cu.

  3. No polishing or coating inside of block.

  4. Overbore of .060 permitted.

  5. Only solid steel connecting rods permitted. No polishing or machine work will be permitted.

  6. Flat top or dish 3 ring pistons only. Piston must not extend above top of block.

  7. Crankshaft with stock stroke must be retained. Minimum weight 50lbs.

  8. Crankshaft must not be Knife-edged. No excessive machining or grinding other than balancing. No drilled main journals. Subject to template inspection by Tech Official.

  9. Wet sump oil system only.

  10. Enlarged oil pan allowed. Kick outs will not be permitted between the bolt holes flange and
    the top of the added sump. Oil pan 4” minimum ground clearance.

  11. No electric fuel pumps allowed.

  12. Aftermarket valve covers allowed.

  13. Aftermarket pulleys allowed.

HEADS:

  1. Stock OEM production steel heads only.

  2. No Vortec heads on built engines.

  3. NO modifications, no porting, polishing, or angle milling. No grinding of any kind. 3 angle valve job ok as per Speedway rule. One cut below valve seat, to bottom of valve guide. Do not radius or blend bottom of cut below valve seat.

  4. Chevrolet 70cc minimum; Ford (Clev) 68cc; Ford (Win) 58cc; Chrysler 68cc minimum.  OEM valve size for cylinder head required. Steel valves required. Valve size maximum:
    Chevrolet 1.94 intake 1.50 exhaust
    Ford Cleveland 2.05 intake 1.65 exhaust
    Ford Windsor 1.89 intake 1.60 exhaust
    Chrysler 1.90 intake 1.60 exhaust

CAM SHAFT: 

  1. Hydraulic or flat tappet cam and OEM diameter lifters with a maximum lift of Chev .480, Ford .512 Dodge .500 at valve with valve lash as ran in race. Lift will be measured at the retainer.

  2. Any steel type timing chain allowed.

  3. Screw in studs and guide plates permitted with any ratio roller rocker arms allowed.

  4. Stud girdles are permitted. Poly lock allowed.

  5. Hydraulic cams will be measured with solid lifter and 0 lash.

INTAKE and SPACER:

  1. Cast Iron two-barrel intake or Edelbrock performer aluminum intakes. Chevrolet #2101 Ford Windsor #2181, Cleveland #2665, #2750 and Chrysler #2176 or P#4532852.

  2. No high-performance intake manifolds permitted. Intakes must be speedway approved.

  3. No porting, polishing, or grinding will be permitted. Do not touch it.

  4. Holley #7448 spacer a maximum ¾” metal spacer with 2 holes (max 1 ½ 1.502) centered in spacer with a straight cut. No Bevels. Spacer Gaskets .065 max thickness.

  5. Holley #4412 spacer a maximum ¾” metal spacer with 2 holes (max 1.690) centered in spacer with a straight cut. No bevels. Spacer gasket .065 max thickness.

  6. All carburetors and spacer plates must meet speedway specifications.

  7. No tapered spacers allowed.

CARBURETOR:

- The Holley 450 carburetor is a 500 top with a 350 bottom. The only 500 tops allowed are 4412 or HP 500 with a 350 bottom part #2300. No modification allowed outside NASCAR rework guidelines.

- The Holley 500 2bbl and Holley 390 4bbl carburetors must conform to the NASCAR rulebook.

See below for rework guidelines:

  1. No polishing, grinding or machine work allowed on any part of the carburetor.

  2. No alterations except choke hardware may be removed and all vacuum ports must be plugged.

  3. Base plate must not be altered in shape or size.

  4. Boosters may not be altered in any manner including size, shape or height of model #.

  5. Any attempt to pull outside air other than through the venturi is not permitted.

AIR CLEANER: 

  1. Round air cleaner element minimum of 12 inches; maximum of 17 inches.

  2. Element must be minimum of 1 ½ “and a maximum of 4 inches in height.

  3. Dry type paper element only. No cold air boxes or cowl induction allowed.

  4. No tubes, funnels or anything which may control the flow of air are permitted.

  5. Air cleaner base must not be above choke horn.

TRANSMISSION and FLYWHEEL ASSEMBLY: 

  1. OEM standard production manual transmissions. Only 3 or 4 speed permitted. All gears must work, no straight cut or machined gears. No top loaders or special production transmissions.

  2. Heavy duty OEM steel clutch permitted. No lightening.

  3. Minimum clutch and flywheel assembly with bolts 33 pounds.

  4. Hydraulic clutch control permitted.

  5. Must have steel bell housing that is speedway approved.

  6. The driveshaft must be of magnetic steel only. The drive-shaft must be painted white with two safety loops attached to the bottom of car.

  7. Tex or Richmond aftermarket transmission with stock type gears permitted.

  8. The 5 ½” clutch package will be allowed with no weight penalty as will the 7 ¼” package and 10 ½”

EXHAUST: 

  1. Headers (4 into 1) will be permitted. No stepped headers. No 180 or crossover allowed. No stainless-steel headers.

  2. Cast iron manifolds permitted.

  3. All LH exhaust must exit behind the driver.

  4. Header wrap permitted.

ENGINE LOCATION: 

  1. Engines may be interchanged from one body manufacturer to another.

  2. Engine location, Ford and GM must follow the current NASCAR rulebook guidelines.

  3. Minimum crankshaft height is 12”, from the center of crank pulley to the ground.

COOLING SYSTEM: 

  1. Aluminum radiators permitted. Any radiator allowed.

  2. Overflow hose recommended.

  3. Antifreeze is not permitted.

  4. Electric fan permitted.

ELECTRICAL SYSTEM: 

  1. Electronic or point type OEM ignition only.

  2. You may run aftermarket distributors.

  3. Only 1 racing coil permitted. (Accell, MSD, etc).

  4. Only one 12-volt battery permitted.

  5. MSD ignition box allowed, analog only. No adjustable timing controls.

  6. MSD claim rule, $300 by speedway or any driver that completed the charger series race.

  7. No open-ended wiring in the driver’s compartment.

  8. Any type of traction devices are not allowed. No computerized systems are allowed.

  9. All ignition systems must be acceptable to speedway officials.

  10. No digital gauges allowed.

FUEL and FUEL SYSTEM: 

  1. Charger cars must purchase five (5) gallons of track fuel from track fuel supply.

  2. All Fuel must pass Speedway Fuel specifications. No oxidizers or additives, fuel must pass track chemical fuel test.

  3. Fuel cells are recommended. Must be securely strapped down with no less than 1/8” steel straps. Fuel cell must be vented high and to the left side.

  4. The maximum capacity allowed is 22 gallons.

  5. Fuel cells must have 8” minimum ground clearance.

WHEELS and TIRES:

  1. Maximum width 10” on all 4. 15” Steel wheels only. All 4 wheels must be same offset.

  2. Air bleeders will not be permitted. No chemical tire treatment allowed.

  3. Tires used for qualifying and race must be approved by the speedway.

  4. Any car tires from any source other than speedway tire building will be disqualified.

  5. Only Florence Motor Speedway purchased track tire required.

WEIGHT w/ ENGINE COMBINATIONS: 

  1. GM 603: 3050 lbs / 1350 lbs / 390 4bbl carb / A one piece open hole solid aluminum carburetor spacer, a maximum 1” in thickness, may be used between the intake manifold and the carburetor. The spacer must be centered on the intake manifold with a single open hole which must be cut perpendicular with the base of the carburetor. Taper, bevels, or any other modifications will not be permitted.

  2. GM 602: 3050 lbs / 1350 lbs / 650 4bbl carb

  3. FORD 347JR: 3050 lbs / 1350 lbs / 390 4 bbl carb/ NO SPACER PLATE

  4. GM 604: 3075 lbs / 1375 lbs / 500 2 bbl carb 4412 / .750” thick two-hole spacer plate /

  5. LMSC Built: 3075 lbs / 1375 lbs / 450 2 bbl carb / .750” thick two-hole 350 spacer plate

  6. DILLON 70cc: 3100 lbs / 1400 lbs / 500 2bbl carb 4412 / .750” thick two-hole spacer plate

  7. ANY STOCK CLIP CAR WITH ANY ENGINE COMBO CAN TAKE 50 LBS OFF FROM LISTED WEIGHT TOTALS ABOVE.

  8. The Holley Ultra XP 500 cfm and tapered spacers will not be allowed.

AMENDMENTS:

  1. These rules are subject to amendments for competition when ample notice has been given by the speedway.

  2. Any car that does not conform to the above rules may be allowed to compete with a weight and/or restrictor plate at the tech committee’s discretion.

  3. Speedway officials may use professional judgment for any infractions for a competitive race program. Rules may be in place for drivers to gain experience.

****ANY RULES YOU DO NOT UNDERSTAND OR YOU NEED CLARIFICATION, PLEASE CONTACT SPEEDWAY OFFICIALS.****

LIMITED LATE MODELS

LIMITED LATE MODEL RULES:

(BY THE 2025 NASCAR RULE BOOK WITH THE FOLLOWING EXCEPTIONS) 

OVERALL CAR WEIGHT (total/right side) - CARB requirements:

1. GM 602 crate: (3000/1300)               390 4bbl / any 1” alum spacer

                           (3025/1325)               650 4bbl / any 1” alum spacer

2. GM 603/ZZ4 crate: (3000/1300)        390 4bbl / any 1” alum spacer

                                   (3025/1325)        650 4bbl / any 1” alum spacer

3. Ford 347 JR crate: (3000/1300)        390 4bbl / any 1” alum spacer

                                  (3025/1325)        650 4bbl / any 1” alum spacer

4. GM 604 crate: (3050/1350)                       500 2bbl HPX or Ultra / any 1” alum spacer

5. Dillon 70cc: (3075/1350)                           500 2bbl HPX or Ultra / any 1” alum spacer

6. LMSC Built (Steel Head): (3050/1350)     450 carb / 350 adapter / any 1” alum spacer

7. Chevy Spec Upgrade: (3125/1415)              450 carb / 350 adapter / .75” 2 hole non tapered 350 spacer  

8. Ford 347 SR crate: (3100/1400)               450 carb / 350 adapter / .75” 2 hole non tapered 350 spacer

9. HMS Enforcer: (3100/1400)                     450 carb / 350 adapter / .75” 2 hole non tapered 350 spacer

Clarification:

450 Carb is 500 top with a 350 bottom. The only 500 Tops allowed are 4412 or HP 500 with 350 bottom pt # 2300. NO modifications permitted outside NASCAR Tech Specs

 

SHOCKS / BUMP STOPS 

- Shocks and Bump Stops will be permitted in accordance with the 2023 NASCAR RULE BOOK

- In addition, AFCO and PRO shocks will be legal WITHOUT BASE VALVES.

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* Must have rocker panels on both sides of the car. The rocker panels must be of matching thickness on both sides with a minimum thickness of .025" thickness, magnetic steel. It will be mandatory by July 1, 2025.

​

* Maximum width of body parts and side skirts between the front and rear tires is 77 1/2". The right door and quarter panel must be flat and not concaved in. 

​

* The rear window must have a vertical brace in it to keep it from pushing in. The rear and side windows must have all the screws / rivets in and tight. 

​

* If any of the body components cannot be fixed, you will add 25 lbs to the right side. 

SUPER TRUCKS

COMPETING MODELS:

  1. 1996-2023 truck models with wheelbase of 110-112 inches.

  2. Trucks with 108 and 109 inch wheelbase must add 25 lbs. to right side.

  3. Tread width of 65 1/2 inches +/- 1/2 inch as raced.           

TRUCK BODIES:

  1. Front and rear windshields must be lexan. No side or quarter windows. May run window vent behind A post, maximum 9” long.

  2. Speedway approved window net must be installed in the driver’s side window opening.

  3. Body height minimum 4 inches, roof height minimum 56 inches with driver measured 10” behind windshield. Rear Spoiler height maximum from the ground– 44”. ALL BODY HEIGHTS, ENGINE, FUEL CELL, AND REAR SPOILER HEIGHTS WILL BE CHECKED ON 4 INCH BLOCKS.

  4. Rear spoiler 5” high with maximum 60” width. Spoilers may have adjustable braces.

  5. Rear spoiler angle must be the same across the spoiler.

  6. Rear spoiler must be centered on the truck, no offset to one side.

  7. No added materials to quarter panels behind the rear wheels.

  8. Wrecker hookup required on front and rear of truck.

  9. Rear bumper cover must be complete and fastened to the rear bumper bar. No cutting of bumper cover.

  10. There will be a measurement from rear axle across quarter panel to farthest end of rear bumper and this measurement will be a maximum 51" with 112” wheel-base.

  11. The only ducting allowed under the front of the race truck will be for the radiator. This duct work must not be wider than and must not extend past the radiator.

  12. All body parts must not exceed the outside edges of the tires on the truck, front or rear except for the front bumper cover.

  13. The truck body must not be skewed on the truck. All bodies must be centered on the vehicle.

  14. The front windshield angle must be no less than 35 degrees when checked in the middle.

  15. For driver safety, insulation will be allowed around the driver area and foot box for heat reduction.

FRAME:

  1. Tubing front sub frame allowed. Stock OEM front sub frame allowed.

  2. Frame rails minimum 2”x 3” x .083 wall thickness between wheels.

  3. Frames must be perimeter style. Front and Rear sub-frames must be centered to roll cage.

  4. Cage must have at least 4 door bars on both sides.

  5. All bars must be as at least 1 ¾ inches x .083 tubing.

  6. Driver’s door bars must be covered by steel plate.

  7. Must have 1 ½ “ windshield bar.

  8. All bars within driver’s reach must be padded.

  9. Roll cage must be at least 43” tall when measured from top of frame rail to top of roll cage.

  10. The roof halo bar must be a minimum of 37” outside to outside. Anything less than 37” will have to add 25 lbs to right side and to the total weight.

  11. A steel interior must separate the driver from the engine compartment and fuel tank.

  12. Floorboard may be raised ten inches to the drive shaft tunnel to the top of the door bar and seal off to allow clearance for headers. No boxed interiors.

  13. A complete speedway approved roll cage.

  14. Roll cage must be centered on the main frame rails. Perimeter style. If your truck has an offset chassis, and there have been no additions to make it a perimeter style, you must add 25 lbs to the right side and total weight.

  15. The right side door boors must match the left side door boors extruding out.

  16. If you have both a narrow halo bar and an offset chassis then you will have to add 40 lbs to the right side and total weight instead of 50 lbs.

FRONT SUSPENSION:

  1. Coil-over suspension allowed.

  2. Screw Jacks allowed on front and rear

  3. Fabricated spindles allowed. One piece billet spindles will NOT be allowed.

  4. Lower A-frames may be Fabricated or aftermarket.

  5. Front lower control arms may be strut rod.

  6. Upper A-frames may be fabricated.

  7. Front sway bar may be OEM or Aftermarket design.

  8. No titanium suspension parts allowed.

STEERING:

  1. Rack and Pinion steering allowed.

  2. OEM type steering and steering box allowed.

  3. Steering components may be aftermarket.

  4. Any type of steering or power steering allowed.

REAR SUSPENSION:

  1. Three link, leaf spring or truck arm suspension allowed.

  2. A metal fabricated pan-hard bar is allowed.

  3. Damper shock permitted on rear suspension.

  4. Rubber bushing, metal bushing, teflon bushings or heim joints allowed.

  5. Three link lower trailing arms may be metal tubing.

  6. Truck arms must be magnetic steel.

  7. Rear sway bar not permitted.

  8. No Titanium rear suspension parts allowed.

  9. All rear suspension parts must be one solid piece with no moving parts.

REAR END:

  1. Rear end may be car, truck, floater, or standard quick change.

  2. No cambered rear ends. +/- .4 Grace. No aluminum tubes. No aluminum yokes.

  3. Detroit Locker or spool only. No torque limiting devices allowed.

  4. Only steel third members (9 inch chunks) allowed.

  5. No titanium rear end parts allowed.

  6. Chains or cables on the rear end to stop traveling when jacked up must be installed with bolt and lock nut. No quick release pins will be allowed. When jacking the car up, the frame must jack up a minimum of 2 inches before the tire clears. If not connected on both ends, it must be removed before you race.

SPRINGS and SHOCKS:

  1. For all NASCAR Advance Auto Parts Weekly Series book for specifics on springs allowed.

  2. May use bump stops on front only.

  3. SHOCK ABSORBERS (Section 1-Z)

A. Shock absorbers and components must be from an approved manufacturer. The approved shock absorbers will be of the revalvable, rebuildable, gas pressurized, mono-tube, deflective disc valve type with an integral gas reservoir. Shock absorbers must provide a resultant force dependent upon piston velocity and must be acceptable to Track Officials. Shock absorbers and components must be used as supplied by the manufacturer and all components must be used in only their respective manufacturers’ shock absorber. Modifications or changes to the shock absorber and internal components will not be permitted. Shock absorbers and components must be available to all Competitors and must meet the following requirements.  As per local Track Rules, oil type shock absorbers will be permitted. Specifications and rules for these oil type shock absorbers will be developed, implemented, governed, and enforced by the individual Track Rules.  

B. The approved shock absorbers and components are as follows: 

  • Penske 7500 Series with only the approved Penske Digressive, Linear and High-Flow Pistons  

  • Bilstein ASN, SN or AS2 Series with only the approve Bilstein Linear U37T Series Pistons #423171 and #403556 

  • C2P NAEX Series with only the approved Linear #62070 and Hi-Flow #40094 Pistons 

  • Advanced Racing Suspensions 4000 Series with only the approved #40094 Piston 

  • PRO PG Series with only the approved Linear/Linear #63 Piston

  • JRI ST/08 Series with only the approved #3803-15 Piston 

  • Blackmagic Shocks (Shadow Racing Products) BML Series with only the approved BML Linear Piston 

  • In addition, AFCO and PRO shocks will be legal WITHOUT base valves.

C. Changes in shock absorber force must not be made by the position of the shock absorber shaft, only by the velocity of the shaft through the compression and rebound stroke.  

D. Track Officials may use a shock absorber and internal components provided by the respective manufacturer as a guide in determining whether a Competitor’s shock absorber and internal components conforms to the specification of the Rule Book. 

E. The only shock absorbers and internal components permitted will be those approved by NASCAR and Track Officials.  

NOTE: The internal bore of the shock absorber body must remain as supplied by the manufacturer. The internal bore diameter of the shock absorber body must be the same from top to bottom. Tapers, steps, grooves, and other misalignments will not be permitted. Modifications which provide position sensitive piston travel will not be permitted. 

F. Shock absorber base valves will not be permitted. 

G. “Steel” deflective disc valve shims must seal the primary metering faces of the single piston in the main shock body. The only shims permitted will be those manufactured, produced and/or recommended by the specific shock absorber manufacturer. Shims must be used in only their respective shock absorbers. Ring shims and bleed shims will be permitted. Floating shims will not be permitted. The shim stack must be of the single pyramid type with the exception that multiple shims of the same size may be stacked together. The inside diameter of the shims must match the shaft diameter with the exception of the outer ring of the ring shim. 

H. Only a single one-piece piston is permitted in the main body with one (1) shim stack on the compression side, and one (1) shim stack on the rebound side. A maximum of three (3) bleed holes may be drilled in the piston. If bleed holes are drilled into the piston, they must be drilled into the port of the piston only. The only pistons permitted are the Linear and High-flow pistons that were submitted by the manufacturer and approved by NASCAR. The piston band must be the original band for the approved manufacturers piston. The piston band and piston band groove in the piston must remain the standard size and must not be altered. 

I. One-piece open style jets that bleed equally in both compression and rebound will be permitted. One-piece jets that control flow in compression only or rebound only will be permitted. Solid plugs in place of open jets will be permitted. Plugs with fixed bleed holes will be permitted. Check ball jets that control flow in compression or rebound only will be permitted. 

J. The gas reservoir maximum outside diameter must not exceed 2.300 inches. External shock absorber gas reservoirs will not be permitted. 

K. The single floating divider piston in the integral gas reservoir must be installed to the manufacturer’s specifications without any modifications. 

L. The gas reservoir must not be filled with any material other than in an inert gas form. Oils or any other types of liquid or materials that are not approved by NASCAR or Track Officials will not be permitted in the gas reservoir side of the shock absorber divider piston.  

M. The shock absorber nitrogen gas pressure must not be less than 50 psi or greater than 150 psi. Gas pressure will be measured at ambient temperature (not to exceed 100 degrees Fahrenheit) by temperature monitoring devices used by Track Officials. Gas pressure will be checked with the shock absorber removed from the race vehicle and fully extended. AZer being charged, at any time, the shock absorbers must fully compress and fully extend the entire length of the shock absorber shaft with the external adjustment (if used) set in any position without any type of mechanical assistance. An external Schrader valve, needle valve, etc. will be required to pressurize the shock absorber with gas. The competitor must have the equipment required to adapt to the technical inspection equipment to check the gas pressure in the shock absorber. 

N. Oils that the viscosity can be changed by any type of electro-magne5c field or by any other means will not be permitted. 

O. Shock absorber shaft diameter must not exceed 0.630 inch and the shaft must not have any sleeves or spacers that could limit the travel of the shaft into or out of the main body. Shock absorber shafts must be solid on all non-adjustable shock absorbers. When single adjustable shock absorbers are used hollow shock absorber shafts will be permitted. 

P. Suspension travel must not be limited by the shock absorber and/or components, or shock absorber mounting location. 

Q. Coil over shock absorbers will be permitted. 

R. Remote or electronically controlled shock absorbers will not be permitted. 

S. A maximum of one (1) shock absorber per wheel will be permitted. 

T. Quick disconnect shock absorber mounts will not be permitted. The shock absorber must be attached with positive nut and bolt mounting fasteners. Adjustable shock absorber mounts of any type will not be permitted. Shock absorbers must be mounted on the vehicle with the gas reservoir to the top. Shock absorber eyelets of different lengths will be permitted but must not limit the travel of the chassis. 

U. Shock absorbers will not be permitted inside of the front or rear coil springs, with the exception of the coil over type springs.  

V. All rear shock absorbers must be mounted behind the rear axle housing. 

W. The rear shock absorbers must not angle inboard towards the center of the vehicle more than 30 degrees from vertical. 

X. Heating pads and/or blankets will not be permitted for warming the shock absorbers.  

Y. Shock absorbers and internal components are subject to inspection at any time by Track Officials.

Z. It is the responsibility of the driver, not NASCAR or Track Officials, to ensure the shock absorbers are used in accordance with the manufacturer’s instructions and specifications. 

BRAKES:

  1. Single or Multi piston metal brake calipers permitted.

  2. Steel disc brakes may be used on front and rear. All 4 wheels must work.

  3. No titanium brake parts allowed.

ENGINES:

ENGINES ALLOWED 

  1. 602 CHEVY CRATE must run with a 390 cfm carburetor with no engine modifying of engine parts.

  2. 603 CHEVY CRATE must run with a 390 cfm carburetor with no engine modifying of engine parts.

  3. 602 AND 603 CHEVY CRATE must run with a 500 cfm carburetor when use rocker arm GM part # 19210724 and adjuster nut part # 88961233 or Scorpion 1.5 rocker arm part #scp1035 with matching adjuster nut. And replacing harmonic balancer with GM part #12551537. And when changing valve springs with competition Cam #2697516.

  4. 604 CHEVY CRATE must run a 500 cfm carburetor. The Holley Ultra XP 500 cfm will not be allowed.

  5. Ford 347 JR CRATE must run 390 cfm carburetor.

  6. Ford 347 SR / 347 SR7 CRATE must run 450 cfm carburetor. The Ford 347 SR7 crate must run a 7000 RPM chip.

  7. Ford, Chevy and Dodge Late Model Stock built engines must run a 450 This engine package may run the 450 carb with any 1” aluminum tapered spacer.

  8.  70CC engines must run a 500 cfm carburetor. The Holley Ultra XP 500 cfm will not be allowed. This engine package may run any 1” aluminum tapered spacer.

70CC engine rules :

  1. Only stock production engines allowed. Chevrolet 350, Ford 351. Chrysler 360 cubic inches are maximum allowed plus over bore.

  2. No coating or polishing inside of block.

  3. Overbore of .060 + normal wear permitted.

  4. Aftermarket solid steel connecting rods permitted. No polishing or machine work will be permitted.

  5. Flat top 3 ring pistons permitted. Piston must not extend above top of block.

  6. Crankshaft with stock stroke must be retained. No excessive grinding or machining, just for balancing purposes only. Subject to template inspection by tech official. Crankshaft must not be knife edged. Minimum weight is #50 pounds for crankshaft.

  7. Wet sump oil system only. Aftermarket pulleys allowed.

  8. Enlarged oil pan allowed. Kick outs will not be allowed between the bolt holes flange and the top of the added sump.

HEADS

  1. Stock OEM steel heads only.

  2. World Products Stock Replacement Head allowed.

  3. No vortec heads on built motors, no angle plug heads allowed.

  4. No angle cutting heads.

  5. No modifications, no porting or polishing. No grinding of any king. 3 angle valve job ok as per speedway rule. One cut below valve seat, to bottom of valve guide. Do not radius or blend bottom of cut below valve seat.

  6. Chevrolet 70cc minimum; Ford (Clev) 68 cc minimum; Ford (win) 58cc.

  7. Stock OEM valve size only.

  8. Valve size maximum: Chevrolet 1.90 intake 1.5 exhaust, Ford Cleveland 2.05 intake 1.65 exhaust, Ford Windsor 1.89 intake 1.6 exhaust. 

CAMSHAFT

  1. Hydraulic or flat tappet cam and OEM diameter lifters with maximum lift of Chev .480, Ford .512 at valve with valve lash as ran in race. Hydraulic lifters will be measured at the retainer after replacing hydraulic lifter with a solid lifter and zero lash. 

INTAKE AND SPACER

  1. GM performer 2101 current design, FORD M2924-P

  2. No porting, polishing, or grinding will be permitted. Do not touch it.

  3. Holley #4412 carb 2bbl spacer must have 2 holes with max 1 11-16” openings. May run the same spacer on the 500 or the 450 carbs.

  4. Holley 390 cfm carb is allowed a 1” solid aluminum spacer with four holes or open spacer.

  5. Holes must centered and cut perpendicular with the base of the carburetor. No tapers

  6. Only 2 gaskets, 1 per side, maximum thickness .056 will be permitted.

  7. No adjustable spacer will be permitted.

  8. All carburetors and spacers plates must meet speedway specifications.

CRATE ENGINES:

  1. The Following Crate Engines must be used as supplied from factory manufacturer. These engines are subject to tear down procedures and legalities is determined by tech committee. The staff at Florence Motor Speedway has invested a lot of time and money to be “up to date” on these engines, therefore make sure the engine is legal or it will be caught. These engines may require different size carbs to equal horsepower between different model #.

  • GM #602

  • Ford# 347JR FORD#347 SR

  • GM #603 GM#604

  1. These engines are designed to cut the cost of racing. Anyone found tampering with these engines will be fined up to $1000 for each offense and loss of championship points.

  2. Crate Motor is a great application for Local Racing if the competitor will leave them alone. Run them as supplied from the factory to ensure legality. Contact Tech Official if you need clarification to this rule.

  3. GM Crate Engines can change valve covers and distributors.

  4. GM crate engines may run aftermarket valve springs with the same diameter, same installed height, and same open pressures as stock crate springs. 

BUILT ENGINE RULES:

  1. ALL BUILT ENGINES BY NASCAR LATE MODEL STOCK CAR RULE BOOK

CARBURETOR

  1. All carburetors are by NASCAR rule book from past years. The Holley Ultra XP will not be allowed.

  2. GM #88958602 Crate engine may use: Holley HP80507-1 390 four-barrel carburetor.

  3. GM #88958603 ZZ4 Crate engine may use: Holley HP80507-1 390 four-barrel carburetor. With crate engines the way it comes from GM

  4. 602 and 603 GM crates with modified engine in rules above must run a 500 carb.

  5. GM #88958604 Crate engine must use: Holley 2bbl “500″

  6. 70CC Engines must use Holley 2bbl “500”

  7. Ford 347 JR Crate Engines: 347JR - Holley HP80507-1 390 four-barrel carburetor

  8. Ford 347 SR Crate Engines: 347 SR -Holley 2bbl “450”

  9. A “450” carburetor is an old-style Holley 500, model number 4412, 350 base plate including the two blending rings in the bottom of the venturi. The built engine package, Line 7 in “Engines Allowed,”, may run the 450 and any 1” aluminum tapered spacer plate. The 70 cc package, Line 8 in “Engines Allowed,” may run any 1” aluminum tapered spacer plate.

AIR CLEANER:

  1. Round air cleaner element minimum of 12 inches; maximum of 17 inches in diameter permitted. Front facial may only be half the diameter.

  2. Top and bottom of air cleaner must be the same size.

  3. Element must be minimum of 1 ½ “and a maximum of 4 inches in height.

  4. Dry type paper element only.

  5. No tubes, funnels or anything which may control the flow of air are permitted.

  6. The base of air cleaner cannot extend higher than carburetor choke horn.

  7. Base of air cleaner on 4-barrel carb no more than 1 ½”above mounting ring of carb.

  8. No cold air boxes or cowl induction allowed.

TRANSMISSION and FLYWHEEL ASSEMBLY:

  1. Automatic, or 4 speed transmissions permitted. May be interchanged.

  2. All gears must be in working order.

  3. 2-speed or 3-speed transmissions, or “speed” transmission allowed. Must add 50 lbs to overall weight for 2 speed transmission.

  4. No centrifugal clutch transmissions allowed.

  5. All trucks must run a steel flywheel in original location.

  6. A metal multi-disc clutch allowed. Minimum disc diameter 5 ½”.

  7. Hydraulic clutch control permitted.

  8. Blow proof bellhousing required. Must have speedway approved scatter shield. No reverse mount starter.

  9. Bottom of bell housing may be cut for clutch service, inspection and ground clearance.

  10. Driveshaft may be steel or aluminum. Driveshaft must be painted white or silver with safety loops attached to the bottom of truck.

EXHAUST:

  1. Headers will be permitted. H-pipes allowed.

  2. Header wrap or coating allowed AROUND DRIVERS COMPARTMENT.

  3. Cast iron manifolds permitted.

  4. All LS exhaust must exit behind the driver.

ENGINE LOCATION:

  1. Engines may be interchanged from one body manufacturer to another.

  2. Chevrolet engine must be centered in chassis (+/- ½”) and center of #1 spark plug hole in head may be setback 2” maximum with the upper ball joint as ran in race.

  3. Ford and Dodge may be set back a maximum of 4 inches from center of spark plug hole in head from upper ball joints on the driver side.

  4. Ford JR 347 and SR 347 crate and Chevy 602, 603, and 604 crates may be set back 2” from center of #1 spark plug hole from upper ball joints.

  5. Minimum crankshaft height is 12”, measured from the center of crank pulley to the ground on all models with driver in truck in center of seat with steering wheel on steering shaft.

COOLING SYSTEM:

  1. Aluminum radiators permitted. Internal or External oil cooler allowed.

  2. All trucks must have overflow hose.

  3. Antifreeze is not permitted. (SEE GENERAL RULES FOR FINE)

  4. Electric fans are permitted.

ELECTRICAL SYSTEM:

  1. Electronic ignition allowed. Distributor may be welded or locked.

  2. Only 1 stock appearing coil permitted. Aftermarket distributor allowed on all engines.

  3. All Distributors maybe welded or locked on all engines.

  4. Only one 12-volt battery permitted. Stock firing order required.

  5. Only one MSD ignition box permitted. No magnetos. No adjustable timing controls.

  6. MSD claim rule, $300 by speedway or any driver that completed the truck series race.

  7. Ignition box must be visible and out of the reach of the driver.

  8. REMOVED: Starter must mount in original location.

  9. No open-ended wiring in the driver’s compartment.

  10. Tachometer must be able to unhook.

  11. No digital readout gauges.

  12. Any type traction devices are not allowed. No computerized systems are allowed.

  13. All ignition systems must be acceptable to speedway officials.

FUEL and FUEL SYSTEM:

  1. Speedway fuel is the only fuel allowed. No mixtures of any kind.

  2. All Fuel must pass Speedway Fuel specifications. Fuel must be same color.

  3. Fuel cells are mandatory and mounting of them must be speedway approved for safety.

  4. Fuel cells must be securely strapped down with no less than 1/8” steel straps.

  5. The maximum capacity allowed is 22 gallons.

  6. Fuel cells must have 8” minimum ground clearance.

  7. Fuel cell must be mounted in approved steel can.

  8. Fuel cell must be mounted in the center of frame rails.

  9. After a main event you may only add 10 gallons of fuel.

  10. No fuel cooling devices allowed.

WHEELS and TIRES:

  1. 10” Maximum width. 15” Steel wheels only.

  2. Air bleeders will not be permitted.

  3. Tires used for qualifying and race must be approved by the speedway.

  4. Any truck tires from any source other than speedway supplier will be disqualified, a $500 fine imposed.

  5. No chemical tire treatment allowed. Durometer and sniffer enforced.

  6. F45 Hoosier Tires is the class tire for the 2020 season.

  7. Serial numbers are recorded to make sure you race the tires that are drawn. 

WEIGHT:

  1. Trucks with 602 can weigh- 2825 pounds total weight with driver/1225 pounds minimum right-side weight with driver.

  2. All trucks will weigh unless otherwise stated in this rule book- 2850 pounds total weight with driver/1250 pounds minimum right-side weight with driver.

  3.  Straight Rail Chassis will weigh- 2900 pounds total weight with driver/1300 pounds minimum right side weight with driver. (50lbs of it must be bolted center bar right door)

*********************************************************

ADDITIONS:

  1. All trucks will be weighed with the driver in a driving position. May fuel up with 10 gallons only after race.

  2. All trucks must have the weight on the back of hood for tech purposes.

  3. Weight of trucks may be increased or decreased to assure an equal race program.

  4. All lead weight must be added to the chassis securely.

  5. No tungsten allowed.

  6. Penalty of $2.00 per pound for any lead lost on race-track and loss of lead.

  7. If a track official addresses a rule infraction that you cannot fix within a race event, you must add 25 lbs on the right side for the next race event. Failure to do so by the following event will result in an additional 25 lb penalty. Twenty-five (25) pounds must be added each week until the issue is fixed. 

AMENDMENTS:

  1. These rules are subject to amendments for competition when ample notice has been given by the speedway.

  2. Speedway officials may use professional judgment for any rule or infractions for a competitive race program. Any truck that does not conform to any of the above rules may be required to add weight and/or restrictor plate determined by the tech committee.

  3. Speedway reserves the right to approve any engine parts, chassis or body parts that were approved for use in the LMSTS that began in 1996.

MINI STOCKS

DRIVERS:

 

  • Minimum age for drivers is fourteen (14) years old.

  • Drivers under sixteen (16) years old must have officials’ approval and parent’s consent from filled out prior to going on track.

  • Drivers may have experience from any other level of racing and still be allowed to participate.

COMPETING MODELS: 

  • Any 1960 and later model with a maximum wheelbase length of 102 inches.

  • Front or rear wheel drive car or truck. No all-wheel drive cars.

  • No two-seaters and convertibles.

CHASSIS AND ROLLCAGE: 

  • The tech person will have the authority to disallow any car with compromised structural integrity or protruding parts that may be dangerous to a competitor.

  • Any chassis used must have come with a 4 cylinder engine option.

  • Complete 6 point center section and rear down bars must be 1 – 1 ½” minimum diameter and .090 wall thickness minimum. No exhaust tubing, or crimped exhaust pipe bends in main cage.

  • Main 4 points of roll cage must be welded to frame rail, or rocker panel. If welded to floor board, it must be welded onto a 6 x 6 metal patch and must be located no more than 6 inches from factory rocker panel.

  • No offset roll cages allowed.

  • Minimum of 4 door bars on driver side, with 1/8 metal plate welded to outside of roll bars.

  • Minimum of 3 door bars on passenger side.

  • All perimeter bars and bumper bars must be shaped with safe and reasonably rounded ends to eliminate puncturing other drivers’ doors, tires, fuel cells, etc. No push bars outside of the front bumper cover.

  • All bars within driver’s reach must be padded.

  • All chassis suspension mounting points must be in stock OEM location. No exceptions. All left to right, height, and “x” measurements must be within ¼” of factory.

  • Rocker panels may be removed and replaced with tubing, provided the front and back of tubing are sealed.

  • All frames must be stock. Unibody frames may be tied together end to end halfway max on frame rails. No X bracing allowed under floor on frame.

  • Front firewall, floorboard, and all suspension points must remain in factory location. No modifying for any reason. If floorboard has rusted or broke, you may patch weld, but do not remove and replace.

  • Must have full front and rear firewalls with no holes, completely sealed. 22-gauge steel minimum for patched sections, no combustible material allowed to fill holes.

  • Must have factory floor plan from front firewall ventricle section above transmission tunnel behind motor to front mount for back seat.

  • Inner structures of fenders, wheel wells, strut towers, and trunk floor may be removed.

  • Frame may be notched for oil filter or fuel pump clearance.

SUSPENSION:

  • Stock OEM style suspension that came on your car.

  • No aftermarket front control arms.

  • Front control arms may be interchanged within same make as long as both sides are the same length.

  • May not lengthen or shorten lower control arms on any make.

  • Stock style upper control arms may be lengthened or shortened for camber / caster adjustment.

  • No upper control arms added in place of stock strut designed car.

  • Any bushing allowed.

  • MUST MEET TRACKING WIDTH RULE OF75".MEASURED FROM OUTSIDE EDGE OF TIRE TO OUTSIDE EDGE OF TIRE.

  • May use any size, type, or arrangement of wheel spacers to make ride width maximum.

  • Wheelbase must be within +/- 1” of stock factory length for car model claimed. Left and right side of car must be within 1” of length of each other.

  • Strut rods on lower control arms such as Pinto and Toyota may be adjustable in length but retain stock mounting points.

  • OEM sway bars only. No splined type. 1 5/16” or 33 MM maximum diameter, mounting optional. End link design optional, may be adjustable on both ends.

  • Heim joints are allowed on sway bar and in place of tie rods for bump steer correction.

  • Any upper strut plate / connection may be used in place of strut tower.

  • Lemans bar between strut towers allowed.

  • Any caster / camber settings allowed.

  • Adjustable rear shackles and slider blocks allowed on leaf spring cars.

  • Front eye of leaf spring must remain in stock location.

  • Rear pan-hard bars allowed only on cars which came stock with them. May be adjustable from under car only and with positive bolt pattern. (No screw jack)

  • Aftermarket upper and lower trailing arms for the rear is allowed.

  • Rear lower trailing arms cannot be adjustable and must be factory length. No heim joints on lower trailing arms.

  • Solid engine and transmission mounts allowed.

  • Spindles, rotors, and calipers must be OEM but may be interchanged within different year models or versions of your same chassis.

  • No aftermarket spindles. Spindles may be strengthened.

  • Drum brakes may be interchanged with disc brakes within your same make.

  • Brake adjusters, flow control, and metering valves allowed but MUST BE OUT OF REACH OF DRIVER and CANNOT BE USED DURING RACE.

  • Single or double master cylinders allowed. Aftermarket pedals allowed and may be relocated.

  • Steering box and rack may be interchanged among same make.

  • Aftermarket power steering pump allowed.

  • Brake air ducts allowed.

  • Brake hats allowed.

  • Drilling of rotor for cooling allowed.

  • Steering quickner allowed.

  • Quick release steering wheel highly recommended.

BODIES:

  • Any stock or aftermarket body, including straight sided dirt, fiberglass, aluminum, or steel aluminum. Open wheel type must submit photos for approval and will be allowed for one race maximum if approved.

  • Full windshield required. Rear side and rear optional. No door side glass allowed. Windshield must be lexan or safety glass laminated. NO PLEXIGLASS.

  • Two vertical braces at least 1” wide x 1/8” thick required on windshield.

  • Side view and rear view mirrors allowed.

  • Side vent for driver cooling allowed.

  • Roof escape flags as required by Bowman Gray are allowed.

  • All doors must be bolted, welded, or riveted shut.

  • No hood scoops, holes in hood, or anything else funneling air to the carburetor.

  • At least four (4) positive fasteners must be used to hold hood and trunk. OEM or fabricated hinges may account for two of these four total.

  • Rear spoilers will be a maximum of 5” tall and 54” wide. The highest point of rear spoiler must be at least 10” lower than the highest point on roof. Rear spoilers may have to be shortened or removed to meet the 10” minimum described. Rear spoilers must be centered on the car. 

  • Spoilers must be mounted at the back of the trunk area near the tail section.

SHOCK, SPRINGS, AND STRUTS: 

  • One (1) steel bodied or strut per wheel. At least one end must be mounted in factory location.

  • Aftermarket racing shocks allowed. Heim join ends allowed.

  • No aluminum bodied shocks allowed.

  • No revalveable or schrader valve type with external reservoir allowed.

  • Strut type can be adjustable and/or replaceable cartridge in housing type.

  • Any aftermarket coil spring allowed. Rates optional. Spring dimensions are optional.

  • At least one end of spring must be in OEM location.

  • No bump stops.

  • Shocks Claim Rule: $150 each shock. Must finish within three positions of car wishing to claim.

ENGINE LOCATION AND TYPES: 

  • Engine must be installed in stock location. There is to be no less than ½” between the back section of the cylinder head and the vertical plane of the stock firewall. No beating firewall back at this location.

  • All engines must use stock OEM parts with the only exceptions stated here. (see engine rules)

  • Four (4) cylinder piston engines only. No rotary engines. You may interchange engines and chassis within your manufacturer line but not across makes. Example: Any Ford in a Ford but no Toyota in a Ford.

  • No turbochargers or superchargers.

TRANSMISSION, FLYWHEELS, AND CLUTCHES: 

  • Automatic or manual transmissions allowed. All gears must function from driver’s compartment.

  • Automatic (manual shift kits allowed. Reverse shift patterns allowed. Internal modifications for durability only. No trick or lightweight internal parts. OEM factory type only. Torque converter must be stock OEM size. Must be factory OEM stall speed. No stall or hollow converters. No aftermarket high performance converters. No valve or any mechanism to transfer transmission pressure allowed. Neutral safety switch must be functional at all times. Modified transmission pan allowed. Transmission cooler size and placement is optional. Cooling lines must have no more than 12” of high pressure rubber tubing. Aftermarket flex plate allowed.)

  • Manual (All gears must be functional from driver’s compartment. (3), (4), or (5) speed transmissions)

  • No aluminum flywheels permitted.

  • Any stock type flywheel and pressure plate combination with a minimum weight of 23 lbs. Weight will include flywheel, clutch disc, pressure plate, and bolts.

  • No aftermarket high performance clutch packs such as 10,000 RPM, ram, center force, etc. permitted.

  • Reinforcement in area of floorboard for safety is required.

  • No aftermarket transmission. Must be factory standard production only. No lightening of internal rotating components.

DRIVESHAFTS: 

  • Standard one (1) piece, minimum diameter of 2 ½”. Steel only.

  • Must be painted white with car number on it.

  • Driveshaft safety loops front and rear mandatory.

REAR ENDS: 

  • Any car or truck rear end. Interchanging allowed within the same make.

  • Mounts on interchanged rear ends must match stock rear end to exact OEM measurements.

  • 9” Ford rear ends are allowed.

  • Any differential: open, welded, full spool, mini spool, locker, limited slip, or helical gear types allowed.

  • No quick change rear ends allowed.

  • Any gear ratio allowed.

  • No cambered rear ends. +/- 0.4 degrees maximum deviation.

  • Any aftermarket axle allowed.

ENGINES:

BLOCK:

  • Must be stock OEM production. No aftermarket blocks.

  • No block is to be coated, polished, or any machine work except what is listed here.

  • No machining to block for aftermarket rod clearance.

  • Blocks cannot be offset bored but may be sleeved with original bore centerline.

  • Stock OEM type rod, camshaft, and crankshaft bearings.

  • No maximum overbore.

  • Aftermarket pulleys and water pump allowed.

  • Crankcase evacuation system to header allowed.

  • Aftermarket oil pan allowed.

CRANKSHAFT:

  • Must be stock OEM cast or steel, no aftermarket such as scat, lunati, etc. allowed.

  • Stock OEM stroke of crankshaft being used must be maintained within +/- .010”.

  • No lightening or knife edging of throws or counterweights.

  • May polish between #4 rod journal and #5 main journal surface areas for the purpose of identifying cracks more easily and eliminating surface stress risers, not to lighten.

  • Engine balancing allowed. Must be done in standard production manner.

  • Stud girdle kit allowed on main bearings.

  • Crankshafts may be interchanged among blocks within the same make with no machining needed. Direct fit applications only.

  • CC must be posted on hood and must be correct for your bore. Engines will be P&G tested regularly.

  • No 2.5 crankshafts allowed in Fords.

III. CONNECTING RODS:

  • Any steel aftermarket or factory rod allowed.

  • Maximum Length For Rods is 5.9 Inches

  • Any Car Running Longer Than Stock Rods Will Not Be eligible For Weight Breaks.

  • May polish stock OEM rods.

  • No hollow aftermarket rods.

  • Toyotas may use H-beam rods if no block machining is needed.

  • Minimum 1.950” diameter rod journal for Fords.

  • Any rod bolt allowed.

PISTONS AND RINGS:

  • Any flat top piston with any number of ring glands allowed.

  • Must have zero deck height.

  • No gas porting.

  • Any steel wristpin allowed. No titanium pins.

  • Any OEM dome piston engine may run any dome piston. The flat part of the dome piston may extend 0.010” above deck height.

  • Any style rings allowed. Minimum two (2) rings per piston.

BEARINGS, FASTENERS, AND GASKETS:

  • All engine bearings must be stock OEM type sleeve bearing. No roller bearings allowed.

  • No titanium fasteners allowed. Any other fastener allowed.

  • Head and main bearing studs allowed.

  • Any brand gaskets allowed. No O-ring style stealing allowed in place of head gasket.

CYLINDER HEAD:

  • Must be stock OEM casting. No aftermarket heads allowed.

  • Heads may be interchanged on blocks within same make only in direct fit applications. Crossbreeding within same make is allowed. Example: 2300 head allowed on 2000 block

  • Angle milling allowed.

  • Two (2) valves per cylinder maximum.

  • Stainless steel OEM configuration valves and swirl type allowed.

  • Valve stems may not be smaller diameter than stock for head being used without weight penalty. If valve stems are smaller than stock diameter, then competitor must drop their left side percentage from 55% to 53%.

  • No titanium valves.

  • Valves may be back cut 30 degrees maximum.

  • Valve stems may not be canted in head.

  • No interior de-burring, polishing, extrude honing, or acid porting allowed.

  • Ports must be stock as cast from OEM.

  • Lifter bore may be machined for solid adjusters.

  • Valves must retain stock diameter head.

  • Any steel or stainless steel retainer / keeper / shims allowed. Any type of valve job allowed. Valve job angles optional.

  • Any valve spring combination or design.

  • Reinforcement on cam boss allowed.

  • Late Model Stock style bowl cut allowed. One (1) angle under the seat, 1” maximum depth of cut but do not touch the valve guide.

  • No blending of bowl cut to ports or rounding edges that bowl cut creates.

  • No roller cam followers allowed except on GM 151 engines.

  • Cam button allowed.

VII. CAMSHAFTS:

  • Any aftermarket hydraulic or solid cam allowed. Cam lift optional without any penalty.

  • Adjustable cam gear allowed.

  • Stock OEM steel or double roller timing chain and gears with hex adjustment allowed.

  • Anti-pump up hydraulic lifters allowed.

  • No lightweight pushrods.

  • Only stock OEM rocker arms and lifters that came OEM in the head being used.

  • Oil return screens allowed.

  • Lifter valley baffles are allowed.

  • Lifters must be stock size for head being used.

  • Roller rocker arms allowed on GM engine only.

VIII. INTAKES:

  • Stock OEM factory intakes with factory part number.

  • Fuel injection intake allowed.

  • No high performance aftermarket intake manifolds.

  • No porting, polishing, coating, dipping, port matching, etc.

  • Intake may only be modified to accept carburetors. No other modifications allowed.

  • Carburetor adapter plate must not protrude down in plenum.

  • All parts must be mass produced items available as stock production over the counter parts. No special tests or marine type parts.

  • Only North American distributed intakes on domestic. Asian allowed on Japanese makes only.

CARBURETORS, SPACERS, AND ADAPTERS: 

  • Holley 350 CFM # 0-7448, # 0-80787-1 OR Holley 500 CFM # 0-4412, # 0-80-583-1. No HOLLEY ULTRA XP 500 CFM ALLOWED.

  • Choke hardware may be removed.

  • All vacuum ports must be plugged.

  • Two (2) gaskets @ .065 maximum allowed.

  • Any carburetor adapter or spacer, 1 ½” thick maximum.

  • Two (2) circular holes, one (1) oval hole, beveled and or tapered allowed.

  • No modification to carburetor for mounting.

  • 350 CFM, 30 CC accelerator pump only.

  • Carburetors will be checked per NASCAR Late Model Stock guidelines.

  • No polishing, grinding, or machine work allowed.

  • No base plate modification.

  • No drilling of additional holes except per the NASCAR rule book.

  • Boosters may be changed.

  • No booster modification to size or shape.

  • Height and location of the boosters must remain per factory specs only.

  • All boosters must remain OEM outside diameter only.

  • Venturi area may not be altered or reshaped in any manner.

  • No altered gaskets, base plates, or drilling holes into the carburetor.

  • No butterflies to be thinned or tapered.

  • Idle holes may be drilled in butterflies.

  • Screw ends may be cut even with shaft, but screw heads must remain standard.

  • No shafts to be thinned or cut at all.

  • Accelerator pump discharge nozzle may be changed.

  • Power valves may be changed.

  • Jets may be changed.

  • No outside air to be pulled through the carburetor other than through the venturi.

  • Anything not wrote in rules, will be teched per the NASCAR Late Model Stock carburetor rules.

AIR CLEANER: 

  • All cars must have a metal air cleaner housing.

  • Aftermarket air cleaner up to 14 inches in diameter x 5 inches tall maximum allowed.

  • Paper element or K&N type allowed.

  • No funneling of any air to the air cleaner or carburetor.

  • Base of air cleaner must be below choke horn.

  • No carburetor hats, baffles, etc.

  • Top and bottom of air cleaner housing must be the same size.

FUEL & FUEL SYSTEM: 

  • Track fuel only.

  • No additives.

  • No fuel cooling devices.

  • Twelve (12) gallon fuel cell maximum.

  • Fuel cell must be mounted in a can made of at least 22-gauge steel.

  • Fuel cell must be mounted in center of trunk area between the frame rails. No more than 2” deviation from center of rear treadwidth.

  • Fuel cell must be protected with a sufficient amount of structure, including a bar below and to the rear of the can.

  • Fuel cell venting high and to the driver’s side recommended.

  • May run high performance mechanical fuel pump or electric. If electric pump is used, you must have roll over valve and safety switch. This must be approved by tech person.

  • Fuel will be checked randomly.

ELECTRICAL SYSTEMS: 

  • Battery must be securely mounted and enclosed to guard the driver from spills or explosions.

  • Batteries must be mounted in trunk or through floorboard but no lower than frame rails.

  • Only 12 volt electrical system allowed.

  • Standard or electronic distributor may be modified for reliability only.

  • Stock type coils only.

  • MSD, Accell, Mallory, etc. Internal parts, coils, or modules are allowed, stock type only.

  • No magnetos.

  • No multi spark discharge boxes (MSD) allowed.

  • Points type allowed.

  • No full aftermarket distributor allowed.

  • No adjustable timing controls.

  • No traction control devices.

  • All wiring in car must be securely insulated and fastened.

  • Any spark plug wires allowed.

  • Any spark plugs allowed.

  • No dual point distributors allowed.

  • Mel’s distributors allowed.

COOLING SYSTEM: 

  • No Antifreeze. See track fine in general rules.

  • Stock cooling system only in stock location.

  • Any radiator allowed.

  • May use water wetter type products.

  • Electric fan allowed.

  • Overflow hose must be mounted to base of windshield passenger side to alert driver in case of overflow or to a sealed catch container in the trunk area.

  • Fabricated mounting for the radiator allowed. Must be mounted between frame rails.

EXHAUST SYSTEM:

Any stock or aftermarket exhaust manifold or header allowed.

  • 4 into 1 and tri-Y style allowed.

  • Exhaust pipes must route to behind the driver’s seat and must extend to the outer edge of the car.

  • No exposed pipes in driver’s area.

  • Exhaust may run through the inside of car if totally boxed, sealed, and approved by tech person.

  • No pipes turned down.

  • Mufflers allowed.

  • Crankcase to exhaust evacuation systems is allowed. Only quality check valves will be permitted.

OILING SYSTEM: 

  • Stock type wet sump only.

  • External oil filter and coolers allowed. Must remain under the hood with steel braided hose and any type fittings. No rubber hose or hose clamps allowed.

  • No dry sump or accu-sump systems allowed.

  • Any aftermarket racing oil pan allowed.

  • Screen kits in oil return system allowed.

  • Oil pan baffles preventing oil from flowing away from the oil pump pickup allowed.

  • Windage trays allowed.

GROUND CLEARANCE: 

  • All heights are measured with the driver in race trim.

  • Front spoiler minimum of 4 inches.

  • Center of crankshaft bolt to the ground, minimum of ten (10) inches.

  • Frame height minimum of 4 inches, measured at the frame rail or rocker panel.

  • Fuel cell and / or fuel cell frame minimum 8 inches from lowest point to the ground.

  • Oil pan minimum to the ground is 4 inches.

WHEEL AND WHEEL SPACERS: 

  • 8” maximum width with minimum of 2” backspace.

  • 13” diameter only.

  • Steel wheel only.

  • Any wheel stud diameter and length allowed.

  • Offsets on all 4 wheels do not have to match.

  • No pressure relief valves allowed.

  • No wheel weights allowed.

  • May use any size, type, or arrangement of wheels spacers to make ride width maximum.

  • New tires must be ran on race event of purchase. 

  • When checked by FMS official, all tires must show above a "50" on the tire durometer gauge. 

WEIGHT: 

  • All weight and weight percentages are measured with driver in car in race trim.

  • WEIGHT BREAKS FOR THE USE OF APPROVED SAFETY EQUIPMENT 25lbs. CONTAINMENT SEATS 25lbs. HEAD AND NECK RESTRAINT. Only if you run stock length rod for the engine you are running. 

  • Advertised engine size in CC and left side weight percentage to be located on the hood, so tech person can read it when you roll onto the scales.

  • 5 gallons of fuel can be added for post-race weigh in.

  • 5 gallons regardless of fuel cell size or number of laps run.

  • All cars will weigh one pound per CC after race with a minimum of 2075 lbs.

  • All Ford engines, minimum weight of 2300 lbs. 1 lb per CC above 2300 CC.

  • Toyota 20R block with 22R head must weigh 1 pound per CC.

  • Ford 2300 head on 2000 block must weigh 2300 lbs.

  • Ford Pinto / Lima style engine with 1.50” intake and 1.75” exhaust valves may compete at 2300 lbs.

  • Maximum left side weight is 55% of the total weight unless told to be less by tech person (fiberglass roof or any other reason deemed by tech person)

  • No dislodged parts can be added back to the car after race to make weight.

  • All lead must be in blocks and painted white with car number on it. All weight must be securely bolted with nylon lock nuts on double nuts.

  • Any chassis design or car make that has an obvious advantage over any other may be subject to weight percentage and weight additions for the sake of close competition. This will be determined by tech person.

SAFETY: 

  • Seat belts must not be any older than 5 years by the date on the belts. 5 point harness minimum. If no date, then replace.

  • Helmet (Snell SA95 or better required)

  • Flame retardant driving suit with minimum SFI-1 rating required. SFI-5 highly recommended.

  • Flame retardant gloves and shoes highly recommended.

  • Neck collar, or head & neck device highly recommended. Example: R3, Hans, Hutchens, etc.

  • Aluminum racing seats only.

  • Approved window net required.

  • 2 ½ lb fire extinguisher with a dial, must be located within reach of driver or a switch to activate a fire suppression system.

  • Master kill switch must be mounted within easy access of driver and also safety crew members from outside of car.

TIRES: 

  • The track approved tire will be the Hoosier 800.

  • Tires must be inspected, approved, and marked prior to race to be eligible for competition.

  • No grooving, siping, camber cutting permitted on the tires. Sniffer, durometer, and black light will be used in pre and post-race inspection. Tires must show above a "50" when checked on the durometer gauge. 

  • Tires are subject to be checked at any time by a track official.

PROTESTS: 

  • Protest entire car, bumper to bumper, $900. ($180 to track, and $720 to winner of protest.)

  • Protest entire bottom end of engine including clutch and flywheel, $500. ($100 to track, and $400 to winner of protest.)

  • Protest the head, carburetor, intake, spacer, and bore and stroke, $300. ($60 to track, and $240 to winner of protest.)

  • Protest just bore and stroke, $100. ($20 to track, and $80 to winner of protest. If this is the protest, the head comes off but the protesting team is not allowed to look at anything dealing with the head.)

  • If protest is not accepted, $25 to track, and the remainder goes back to the team that protested.

  • Teams found illegal, by way of protest and teardown procedures will lose all points and money for the current race. Other point penalties may be in order at the decision of the tech person.

  • Illegal parts will be marked and returned at the tech person’s discretion. 

*** ALL RULES SUBJECT TO CHANGE TO KEEP COMPETITION FAIR FOR EVERYONE ***

STREET STOCKS

2024 FLORENCE MOTOR SPEEDWAY STREET STOCK RULES

1.0 - ENGINE/CARB/WEIGHT COMBINATIONS

ENGINE

MIN WEIGHT (BEFORE RACE)

MAX LEFT SIDE WEIGHT %

MAX REAR WEIGHT %

CARBURETOR

Built                   3200     55%.    49 %.    350

GM 602 Crate   3200     55 %.    49 %.    500

GM 603 Crate.  3275.    55 %.    49%.     500

*Yellow book blueprinted crates must add 75 lbs. Ex: Decking Block to specs, cutting cylinder heads to

minimum cc’s, no narrow bearings, etc.

​

2.0 - GENERAL ELIGIBILITY

  1. Participants must be at least 12 years of age.

  2. American made cars only.

  3. No convertibles, station wagons, or pick-ups.

  4. Camaros, Novas, and Firebirds will be allowed but must retain stock rear leaf spring suspension.

  5. Entire interior must be removed.

  6. All holes must be patched in firewalls and floor pans.

  7. Two-way radios will be permitted for use.

  8. All cars must have a spotter in the spotter’s stand for every race.

​

3.0 - WEIGHT RULES

  1. Cars will be weighed pre OR post qualifying and must meet minimum weights. Cars will be weighed again post-race and will be allowed 1 pound per lap burn off. (Ex. 50 lap race = 50 lbs burn off)

  2. No fuel, water or oils may be added after the race to any cars.

  3. Maximum 49% percent rear weight checked with car filled with gas.

  4. All cars maximum 55% left side weight.

  5. Declared weights (including any penalties for engine, body, etc.) must be clearly marked on driver side window with sticker.

  6. Lead will only be allowed in MINIMUM of 5 lb pieces.

​

4.0 - CHASSIS/FRAME

​

4.1 - GENERAL

  1. Frame must remain stock specs from front of steering box to center of rear-end housing or subject to weight penalty.

  2. Full frame car must remain full frame.

  3. Frame must be same dimensions from front to back (length and width).

  4. Frame and cage may be tied and reinforced together by rectangle, square or round tubing for safety.

  5. Front clip must be OEM and may be notched for fuel pump and oil pan clearance.

  6. Cars must have a complete steel firewall and floor pans. No boxed Interior. Sheet metal must be lower than driveshaft tunnel.

  7. Any car that does not have an OEM floorboard will be assessed a 50 lb weight penalty.

​

4.2 - WHEELBASE

  1. Wheelbase must be within 1″ of factory specs for make and model of car with a minimum of 105”, allowing 1” tolerance for alignment.

  2. Any car that is not within 1″ of factory wheelbase specs will be allowed to compete with a 100 lb. weight penalty.

  3. Wheelbase must be within 1” from side to side.

​

4.3 - RIDE HEIGHT

  1. Minimum ride height for the body, chassis, and any component mounted to the body or chassis is 5″.

  2. Minimum ground clearance for oil pan, sway bar, exhaust pipes, and headers is 3″.

​

4.4 - REAR END

  1. A floater rear end will be allowed. Straight spine only.

  2. OEM Limited Slip, OEM Open, Locked Up Spool, or Detroit Locker Allowed.

  3. No Gleason or Gear Driven Devices allowed. No Tru-Trac allowed.

  4. No cambered rear ends allowed (max .4 degrees).

  5. No rear gear rule.

  6. Steel third members.

​

4.5 - TREAD WIDTH

  1. Maximum tread width for front and rear is 66 ½” measured from outside of left tire to inside of right tire at spindle height.

​

4.6 - SWAY BAR

  1. Front sway bars must be stock type or Howe type.

  2. Maximum diameter 1.375”.

  3. No rear sway bars allowed.

​

4.7 - FRONT SUSPENSION

  1. Cars must retain stock OEM spec parts.

  2. Lower A-frames must be in stock mounts and stock locations.

  3. UNALTERED lower A-Frames must remain stock OEM and must be same length on right side and left side excluding ball joints and bushings.

  4. Lower A-frames, Spindles, trailing arms, and pitman arms must remain stock OEM parts.

  5. Centerlink may be aftermarket.

  6. Upper A-frame mounts may be altered.

  7. Tubular upper A-frames may be used.

  8. Tie rods may be steel sleeve with steel heims. Heim joints allowed with washer bigger than heim joints.

  9. Front hubs and rotors must be same size and in OEM location and not be lighter than OEM stock.

​

4.8 - REAR SUSPENSION

  1. Leaf spring suspension can have rear adjustable shackle plates to raise or lower car since there is no screw jacks.

  2. A leaf spring car will be allowed adjustable lowering block to straighten rear end.

  3. A trailing arm car will be allowed eccentric or steel heims to be able to straighten rear end.

  4. Truck arms will not be allowed on any chassis.

  5. Pinion wedges or adjustable top links allowed to adjust pinion angle.

  6. Chassis hookups must be OEM for make and model chassis.

  7. For any car, if your rear suspension chassis hookups/pickup points are changed or altered from stock OEM design you must add 100 lbs to total weight. Including an adjustable track bar on frame connection.

​

4.9 - SPRINGS AND SHOCKS

  1. One steel shock or strut per wheel, $175 each claim rule.

  2. No travel limiting devices of any kind allowed. No coil binding of springs, chassis stops, or bump stops.

  3. Strut equipped cars may take guts out of struts and mount an external shock on car.

  4. Ride heights can be checked at any time during the event.

​

5.0 – ENGINES

​

5.1 - CRATE ENGINES

​

5.1.1 - GENERAL ELIGIBILITY

  1. The following crate-type engines will be permitted and must be used as supplied by the manufacturer and/or per the specifications manual provided by the manufacturer: i) General Motors #88958602 / ii) General Motors #88958603 is legal with a 75 lb weight penalty.

  2. Crate motor technical specifications will be based on the following manual: i) GM Performance Parts Circle Track Crate Engine Technical Manual – Revised May 2010

  3. Crate engines are designed to cut the cost of racing. Run them as supplied from the factory to ensure legality. Any competitor found to be tampering with these engines will be disqualified and forfeit monies and points won.

​

5.2 - BUILT ENGINES

​

5.2.1 - GENERAL ENGINE CHARACTERISTICS

  1. Only standard production engines from manufacturer allowed. GM 350 cubic inch maximum, Ford 351 cubic inch maximum, and Chrysler 360 cubic inch maximum.

  2. Maximum of .060 overbore permitted.

  3. No high performance parts allowed unless listed below.

  4. No polishing or coating any parts including inside of block.

  5. No electric fuel pumps

  6. OEM Stock or OEM replacement parts for OEM cubic inch including cylinder heads, pistons, crankshaft, and steel connecting rods only.

  7. Flat top or dish three ring pistons are permitted. Pistons may have min “two eyebrows”.

  8. Crankshaft with stock stroke must be retained. 50 lbs min weight. Crank journals may be ground for undersize bearings. No lightening or drilling. No other machine work will be permitted.

  9. Enlarged OEM oil pan permitted.

  10. OEM stock production steel heads only with OEM steel valve size and combustion required.

  11. Piston must not extend above top of block.

  12. Four bolt-main blocks permitted.

  13. Aftermarket pulleys allowed.

  14. Unaltered Edelbrock 2101 or 2116 or steel intake allowed on built engine.

  15. 602 GM Crate intake ok.

​

5.2.2 - HEADS AND CAMSHAFT

  1. Stock production steel heads only. No angle plug heads. Vortec heads must have a restrictor plate on a .450-.480 cam lift built vortec head engine with a max 1.357 spacer plate adapter with no bevel. No restrictor plate required on low lift camshaft (.449 and under). Stock Replacement (SR) head will be allowed with a 100-pound penalty.

  2. NO modifications, no porting or polishing. No grinding of any kind. Standard 3 angle valve job allowed.

  3. Chev 70cc min; Ford (Clev) 68cc; Ford (Win) 58cc; Chrysler 68cc min. Chev Vortec 60 cc min.

  4. OEM valve size for cylinder head required. Steel valves required. Any Chev head with cc’s that are below minimums or any valves bigger than 1.94/1.50 will be required to add a 100 pounds or 50 pounds for each. Tech Man may approve other combos with a weight penalty.

  5. Cam and lifters solid or hydraulic with a maximum lift of Chev .480, Ford .512, Dodge .500. Lift will be measured at the valve retainer as run in the race. Any Ratio Rocker to achieve max lift is ok! Any Cam that lifts under .450 or over .480 is eligible for a weight break/carb or weight penalty at tech discretion.

  6. Stock OEM valve spring and retainers. Aftermarket rocker arms allowed. Poly- locks ok. Studs may be pinned, screw-in studs and guide plates permitted. Valves must be steel.

  7. Valve size maximum: a) Chevrolet 1.94 intake 1.50 exhaust // b) Ford Cleveland 2.05 intake 1.65 exhaust // c) Ford Windsor 1.89 intake 1.60 exhaust // d) Chrysler 1.90 intake 1.60 exhaust

  8. Any engine that does not conform to the above engine rules may be able to add weight and/or restrictor plate to be able to race.

​

5.3 - GENERAL ENGINE RULES (ALL ENGINES)

​

5.3.1 - CARBURETOR

  1. Holley 350 CFM 2-barrel carburetor (HP Part# 0-7448 or 0-80787-1) allowed on built or crate engines.

  2. Holley 500 CFM 2-barrel carburetor (HP Part# 0-4412C or 0-80583-1) allowed on crate engines only.

  3. Note: New style Holley 500 CFM “Ultra XP” carburetors not allowed.

  4. Note: New style cast aluminum 4412 not allowed.

  5. No alterations except choke hardware may be removed and all vacuum ports must be plugged.

  6. No polishing, grinding, or machine work allowed on any part of carburetor.

  7. Only stock passenger car OEM boosters allowed. No modifications allowed. No bevels.

  8. Base plate must not be altered in shape or size.

  9. All carburetors must have choke horn. Choke mechanism may be removed.

  10. Any attempt to pull outside air other than through the venturi is not permitted.

​

5.3.2 - CARBURETOR SPACER PLATE/GASKETS

  1. Crate Engines: a 3/4″ centered non-adjustable aluminum carburetor spacer plate is allowed with a onepiece gasket (maximum thickness of.065 inch) on each side of the spacer plate. Carb spacer must be straight cut, no bevel. No Coated or Anodized Spacers allowed.

  2. Built Engines: a 3/4″ centered aluminum carburetor spacer plate is allowed with a one-piece gasket (maximum thickness of.065 inch) on each side of the spacer plate. No Coated or Anodized Spacers allowed.

  3. Air Cleaner base must not be above choke horn.

​

5.3.3 - EXHAUST

  1. Headers allowed.

  2. Exhaust must not be over 3 ½” diameter. May exit from underneath the car.

  3. Exhaust may exit the right or left side of the car for safety.

  4. No dr. gas or merge collectors.

  5. If exhaust exits out the door it must be lower than driveshaft tunnel with as minimal floor trimming as possible.

  6. Exhaust must be covered in 24-gauge steel.

  7. No header wrapping.

​

5.3.4 - IGNITION/ELECTRICAL

  1. A HEI style aftermarket distributor may be used and may be locked for the built motor.

  2. Coil and module must remain in distributor.

  3. No 16V systems allowed.

  4. No traction control devices of any kind will be allowed.

  5. No electric fuel pumps allowed.

​

5.3.5 - COOLING SYSTEM

  1. Aluminum radiators permitted.

  2. Water only, no antifreeze permitted.

  3. Radiators must be stock appearing and installed in the stock location.

  4. All air to the engine must pass through the radiator. No ducting or directing air to the carburetor allowed.

​

5.3.6 - ENGINE LOCATION

  1. Engines may be interchanged from one body manufacturer to another.

  2. A full steel engine firewall may be notched and plated or moved back to allow engine to be located. Excessive moving or cutting could result in weight penalty by tech official.

  3. Engine must be centered in chassis. #1 spark plug in line with upper ball joint.

  4. Maximum crankshaft height is 12” measured from the center of crank pulley to the ground.

​

5.3.7 - AIR CLEANER

  1. Standard round air cleaner only.

  2. No fresh air or induction systems allowed.

  3. No directing fresh air to the carburetor.

  4. No flow control air cleaners allowed.

​

6.0 - DRIVELINE

  1. Stock OEM type working torque converter, min. 10”.

  2. No lock ups

  3. Straight Drive Clutches and pressure plates must remain OEM stock.

  4. No lightening allowed.

  5. Clutch pressure plate, disc, flywheel, and flywheel bolts must weigh 33 lbs. minimum.

  6. Standard OEM production transmissions 3 or 4 speeds will be allowed to compete.

  7. All gears must work.

  8. No overdrive gears allowed.

  9. Must use a steel blow proof bell housing if using OEM stock type clutch.

  10. 7 ¼ or larger metallic clutch will be allowed with a 75lb weight penalty and may use a metal bell housing.

  11. A hydraulic throw out bearing will be allowed.

  12. Starters must mount in stock location.

  13. Steel driveshaft only. Must be painted white with at least one driveshaft loop.

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7.0 - BODIES

  1. Bodies must be steel, absolutely stock appearing - no chopping or lowering of bodies in any way.

  2. Factory OEM roof must be used. 50 pounds must be added for ANY type of other roof than steel roof.

  3. Aftermarket fiberglass roof allowed with weight penalty.

  4. The top of the rear quarters must be OEM.

  5. Aftermarket OEM replacement front fenders and lower quarters may be used.

  6. The hood, deck lid and doors may be aftermarket.

  7. Front of hood must be securely fastened.

  8. Metal rear deck must be securely fastened.

  9. Third generation Camaros are allowed in the series.

  10. Non-approved Street Stock body is subject up to 50 lbs weight penalty or restrictor plate. a)Penalties assessed for each non-steel section of the body broken down into 4 parts: Rear quarters, doors, front fenders, and roof. If you have 1 or 2 of those panels non-steel add 25 lbs to total weight. If you have 3 or 4 of those panels non-steel add 50 lbs to total weight.

  11. A maximum 5″ tall x 60″ wide spoiler will be allowed (300 max square inches). Factory spoilers size allowed.

  12. Hood scoops will be allowed. Open at windshield is ok.

  13. Rear tail must be enclosed with a stock appearing bumper cover.

  14. No right side windows allowed.

  15. Vent windows allowed 12-inch max and will be checked before race.

  16. No current aftermarket LM body.

  17. All bodies must be tech man approved.

  18. All body parts must be securely fastened. Any competitor with body parts that appear to be loose or not securely fastened will be black-flagged.

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8.0 - BRAKES

  1. Single metal piston brake calipers OEM design allowed and all 4 brakes must work.

  2. Brake proportion valve and/or brake bias allowed but must be out of reach of the driver.

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9.0 - TIRES/WHEELS

  1. Teams will compete on scuff 10″ Hoosier race tires purchased from the track.

  2. No softener or tire treatment of any kind allowed.

  3. Racing wheels allowed with a maximum width 10”.

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10.0 - SAFETY

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10.1 - ROLL CAGE

  1. Minimum 4-point roll cage mandatory, two points in front of the driver and two behind.

  2. Mandatory at least 4 door bars on left side, 3 door bars on right side.

  3. Cage must be welded in a professional manner and is subject to approval by tech personnel.

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10.2 - FIREWALL

  1. Car must have a front and rear firewall between the driver, engine compartment, and fuel cell area. Minimum height 10” from ground.

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10.3 - BATTERY

  1. Battery must be in a full closure box and be securely fastened in front of rear end or in driver’s department.

  2. Master On/Off switch must be installed and easily accessible by safety crew.

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10.4 - SEATS

  1. Aluminum factory made racing seats required.

  2. Absolutely no homemade seats.

  3. Seats must be mounted in a manner acceptable to series officials. At least 6 bolts in seat.

  4. Seats may not be mounted to the floor pan.

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10.5 - SEAT BELTS

  1. Seat belts must be a 5-point harness type.

  2. Seat belts must be no older than 5 years old.

  3. Seat belts must not be mounted to the floor pan.

  4. Seat belts must not cross areas that may cut the belts, i.e. not across sheet metal attached to a roll bar.

  5. Seat belts must be replaced if they are worn or the edges are frayed.

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10.6 - WINDOW NET

  1. An approved window net must be installed on the driver’s side window. Full size window nets only.

  2. Window net must release from the top and drop down.

  3. Window net bars must be substantial enough to contain the drivers arms in the event of a rollover.

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10.7 - FIRE EXTINGUISHER

  1. All cars are recommended to have an onboard fire extinguisher.

  2. Extinguisher should be mounted so the charge gauge can be checked by series officials.

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10.8 - FUEL CELL

  1. A made for racing fuel cell (maximum 22 gallons) with foam is recommended.

  2. Fuel line must run through steel tubing if running through driver’s compartment. If running under car must be securely fastened.

  3. All cars must run 100% track race fuel or 100% non-ethanol pump gas. No mixing of gas or additives.

  4. Fuel line through car must be painted red.

***We reserve the right to change or adjust these rules at any time to ensure fair competition. This could include but is not limited to adding/reducing weight and/or adding a restrictor plate as determined by tech officials. All decisions by officials are final.***

URA FLORENCE CLASS RULES

Below you will find class rules for Late Models, Chargers, Super Truck, Limited Late Model, Mini Stock, Street Stock, & Race Procedures.

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