Stock Car Rules
Updated 5/3/2023
RULE BOOK DISCLAIMER;
The rules and/or regulations set forth herein are designed to provide for the orderly conduct of racing events and to establish minimum acceptable requirements for such events. These rules shall govern the condition of all events, and, by participating in these events, all participants are deemed to have complied with these rules. NO EXPRESSED OR IMPLIED WARRANTY OR SAFETY SHALL RESULT FROM PUBLICATIONS OF OR COMPLIANCE WITH THESE RULES AND/OR REGULATIONS. They are intended as a guide for the conduct of the sport and are in no way a guarantee against injury or death to a participant, spectator or official.
The race director shall be empowered to permit reasonable and appropriate deviations from any of the specifications herein or impose any further restrictions that in his opinion do not alter the minimum acceptable requirements. NO EXPRESSED OR IMPLIED WARRANTY OF SAFETY SHALL RESULT FROM SUCH ALTERATION OF SPECIFICATIONS. Any interpretation or deviation of these rules is left to the discretion of the officials. Their decision is final. THE MANAGEMENT OF OKLAHOMA SPORTS PARK (OSP) (ADA, OKLAHOMA) The rules and/or regulations set forth herein are designed to provide for the orderly conduct of racing events and to establish minimum acceptable requirements for such events. These rules shall govern the condition of all events, and, by participating in these events, all participants are deemed to have complied with these rules. NO EXPRESSED OR IMPLIED WARRANTY OR SAFETY SHALL RESULT FROM PUBLICATIONS OF OR COMPLIANCE WITH THESE RULES AND/OR REGULATIONS. They are intended as a guide for the conduct of the sport and are in no way a guarantee against injury or death to a participant, spectator or official.
The race director shall be empowered to permit reasonable and appropriate deviations from any of the specifications herein or impose any further restrictions that in his opinion do not alter the minimum acceptable requirements. NO EXPRESSED OR IMPLIED WARRANTY OF SAFETY SHALL RESULT FROM SUCH ALTERATION OF SPECIFICATIONS. Any interpretation or deviation of these rules is left to the discretion of the officials. Their decision is final.
IF IT DOESN’T SAY YOU CAN, THEN YOU CAN’T!
-------------------------
CHASSIS
Any American OEM full body rear wheel drive passenger car, 1964 or newer, full frame or unibody. Minimum 107.5 inch wheelbase, maximum one inch difference from side to side. Frame must match body - GM to GM, Ford to Ford, Chrysler to Chrysler - AND wheelbase to wheelbase. Exceptions are: 1980 or newer Ford two door unibody may be installed on 1978-1987 GM full frame OR Ford full frame (shortened to minimum 107.5 inch wheelbase). Chrysler engine may be put in 1978-1987 GM full frame, and may use 1995 or newer two door Chrysler unibody. Rear of frame behind rear tires, no further forward than one inch behind factory seam, may be replaced in OEM location with two inch by three inch steel tubing with 0.095 inch wall thickness. Factory seam must remain visible. Unibody must tie rear frame to front frame. Frame may be “X” braced.
ROLL CAGE:
Main cage must consist of continuous hoops, minimum 1.75 inch O.D. tubing, with a minimum wall thickness of 0.095 inch, low carbon or mild steel recommended. Four-post roll cage required, front down bars and rear hoop must be welded to OEM frame. Driver’s head must not protrude outside cage with helmet on. Rear hoop must have “X” brace, consisting of one full horizontal and one full diagonal bar, minimum 1.25 inch O.D. with 0.083 inch wall thickness. Front down bars must be tied together, passenger side front down bars must be maximum 11 inches in from top of door. Must be minimum 40 inches between outside edge of front and rear down bars at top of door panel. Top halo must be minimum 40 inches across, and 29.5 inches front to rear, outside to outside. Rear hoop may be maximum 12 inches in from bottom of opera window. Minimum one cross bar in top halo. May have maximum two horizontal bars, (in addition to bar tying front frame horns together) for radiator protection; must be behind bumper, within confines of body, no wider than stock frame horns. Required rear kickers (down bars) and engine hoop must be minimum 1.25 inch OD tubing, with 0.083 inch wall thickness. Fuel cell protection required, must be mounted frame rail to frame rail, no higher than fuel cell, inside trunk area with maximum 1.75 inch OD tubing. All bars must be inside body. Foot protection bar required.
DOOR BARS:
All door bars and uprights must be minimum 1.75 inch O.D. with 0.095 inch wall thickness. Minimum three door bars, both sides, parallel to ground, and perpendicular to driver. Minimum four uprights tied from frame to top door bar on driver side, and minimum three uprights on passenger side. Steel door plates, 18 gauge or 0.049 inch minimum thickness, must be securely welded to outside of door bars on driver’s side. Plate must cover area from top door bar to frame (1) and from rear down post to five inches in front of seat. Must be visible for inspection.
BODY:
Stock appearing body, must have body lines. Fabricated steel or aluminum bodies ok but must be strictly stock appearing and in stock location. Floorboard may be fabricated steel but must remain full front to rear and in strictly stock location. Firewall may be fabricated steel and can be no further back than oval hole. Aftermarket/Fabricated firewall must be straight up and down(vertical). Aftermarket fiberglass roof allowed but MUST be stock replacement roof with stock appearing pillars (example performance bodies part #1015-81W). A 5” spoiler is allowed with a maximum 5” tall by 7” long sideboard. Stock appearing plastic nose and tail allowed but must match make of car/body. No fender flares allowed. The intent is for this to be a stock car class with as close to stock appearing bodies as possible. Stock bumpers or tube bumpers ok, must cut wrap around off the ends. No sharp edges. No bars connected to bumpers. No cow killer bumpers. All cars must have tow hook/chain on front and rear. Air Filter guards/deflectors are limited to 2" in length measured from front to back.
FRONT SUSPENSION:
All components and mounts must be steel, unaltered OEM, in OEM location and match frame. Rubber, nylon or steel lower A-frame bushings only - no offset or bearing type. No sway bars. Exceptions are: weight jacks allowed - must be in original centerline of spring tower; OEM upper A-frame mount may be moved or replaced with aftermarket steel non-adjustable mount matching upper A-frame bolt on design; OEM or OEM replacement ball joints allowed. For 1978-1987 GM mid-sized metric frame, OEM upper A-frame may be replaced using aftermarket upper A-frame. Shock location may be moved and may go through center of aftermarket upper A-frame, but frame cannot be altered in any way. Single hole shock mounts only. Tie rod adjusting sleeve may be replaced with swedge tube. No suspension stops of any kind allowed. Outboard shocks are allowed.
STEERING:
Steering must remain stock. Steering boxes must remain in stock location. Aftermarket steering wheel and quick release steering coupling are recommended. Quickeners or Quick steer boxes allowed.
SHOCKS:
One steel nonadjustable unaltered shock per wheel. All shocks must completely collapse at any time. No external or internal bumpers or stops. No coil over, air, or remote reservoir shocks. No Schrader or bladder type valve allowed. No coil over eliminators. One or all shocks may be claimed per event for $100 each, must finish on the lead lap, and must notify official within 15 minutes of race.
SPRINGS:
One steel spring per wheel only, or steel leaf spring if equipped OEM. Minimum 4.5 inches O.D., maximum 16 inch free height, non-progressive coil spring only. No spring rubbers allowed.
REAR END:
Quickchange, 9 inch Ford, or floater rear ends allowed. Steel tube rear ends or aluminum quick change axle housing may be used.
SUSPENSION
WEIGHT
Minimum weight, including driver, is 3000 pounds. 3050 with aluminum heads.
BRAKES
Must have 4 wheel brakes, option to run with 3 or 4
TIRES AND WHEELS
8 inch or 10 inch wheels. Used asphalt pull-offs. Steel wheels only. No bleeders allowed.
ENGINE
SAFETY
See general rules.
The rules and/or regulations set forth herein are designed to provide for the orderly conduct of racing events and to establish minimum acceptable requirements for such events. These rules shall govern the condition of all events, and, by participating in these events, all participants are deemed to have complied with these rules. NO EXPRESSED OR IMPLIED WARRANTY OR SAFETY SHALL RESULT FROM PUBLICATIONS OF OR COMPLIANCE WITH THESE RULES AND/OR REGULATIONS. They are intended as a guide for the conduct of the sport and are in no way a guarantee against injury or death to a participant, spectator or official.
The race director shall be empowered to permit reasonable and appropriate deviations from any of the specifications herein or impose any further restrictions that in his opinion do not alter the minimum acceptable requirements. NO EXPRESSED OR IMPLIED WARRANTY OF SAFETY SHALL RESULT FROM SUCH ALTERATION OF SPECIFICATIONS. Any interpretation or deviation of these rules is left to the discretion of the officials. Their decision is final. THE MANAGEMENT OF OKLAHOMA SPORTS PARK (OSP) (ADA, OKLAHOMA) The rules and/or regulations set forth herein are designed to provide for the orderly conduct of racing events and to establish minimum acceptable requirements for such events. These rules shall govern the condition of all events, and, by participating in these events, all participants are deemed to have complied with these rules. NO EXPRESSED OR IMPLIED WARRANTY OR SAFETY SHALL RESULT FROM PUBLICATIONS OF OR COMPLIANCE WITH THESE RULES AND/OR REGULATIONS. They are intended as a guide for the conduct of the sport and are in no way a guarantee against injury or death to a participant, spectator or official.
The race director shall be empowered to permit reasonable and appropriate deviations from any of the specifications herein or impose any further restrictions that in his opinion do not alter the minimum acceptable requirements. NO EXPRESSED OR IMPLIED WARRANTY OF SAFETY SHALL RESULT FROM SUCH ALTERATION OF SPECIFICATIONS. Any interpretation or deviation of these rules is left to the discretion of the officials. Their decision is final.
IF IT DOESN’T SAY YOU CAN, THEN YOU CAN’T!
-------------------------
CHASSIS
Any American OEM full body rear wheel drive passenger car, 1964 or newer, full frame or unibody. Minimum 107.5 inch wheelbase, maximum one inch difference from side to side. Frame must match body - GM to GM, Ford to Ford, Chrysler to Chrysler - AND wheelbase to wheelbase. Exceptions are: 1980 or newer Ford two door unibody may be installed on 1978-1987 GM full frame OR Ford full frame (shortened to minimum 107.5 inch wheelbase). Chrysler engine may be put in 1978-1987 GM full frame, and may use 1995 or newer two door Chrysler unibody. Rear of frame behind rear tires, no further forward than one inch behind factory seam, may be replaced in OEM location with two inch by three inch steel tubing with 0.095 inch wall thickness. Factory seam must remain visible. Unibody must tie rear frame to front frame. Frame may be “X” braced.
ROLL CAGE:
Main cage must consist of continuous hoops, minimum 1.75 inch O.D. tubing, with a minimum wall thickness of 0.095 inch, low carbon or mild steel recommended. Four-post roll cage required, front down bars and rear hoop must be welded to OEM frame. Driver’s head must not protrude outside cage with helmet on. Rear hoop must have “X” brace, consisting of one full horizontal and one full diagonal bar, minimum 1.25 inch O.D. with 0.083 inch wall thickness. Front down bars must be tied together, passenger side front down bars must be maximum 11 inches in from top of door. Must be minimum 40 inches between outside edge of front and rear down bars at top of door panel. Top halo must be minimum 40 inches across, and 29.5 inches front to rear, outside to outside. Rear hoop may be maximum 12 inches in from bottom of opera window. Minimum one cross bar in top halo. May have maximum two horizontal bars, (in addition to bar tying front frame horns together) for radiator protection; must be behind bumper, within confines of body, no wider than stock frame horns. Required rear kickers (down bars) and engine hoop must be minimum 1.25 inch OD tubing, with 0.083 inch wall thickness. Fuel cell protection required, must be mounted frame rail to frame rail, no higher than fuel cell, inside trunk area with maximum 1.75 inch OD tubing. All bars must be inside body. Foot protection bar required.
DOOR BARS:
All door bars and uprights must be minimum 1.75 inch O.D. with 0.095 inch wall thickness. Minimum three door bars, both sides, parallel to ground, and perpendicular to driver. Minimum four uprights tied from frame to top door bar on driver side, and minimum three uprights on passenger side. Steel door plates, 18 gauge or 0.049 inch minimum thickness, must be securely welded to outside of door bars on driver’s side. Plate must cover area from top door bar to frame (1) and from rear down post to five inches in front of seat. Must be visible for inspection.
BODY:
Stock appearing body, must have body lines. Fabricated steel or aluminum bodies ok but must be strictly stock appearing and in stock location. Floorboard may be fabricated steel but must remain full front to rear and in strictly stock location. Firewall may be fabricated steel and can be no further back than oval hole. Aftermarket/Fabricated firewall must be straight up and down(vertical). Aftermarket fiberglass roof allowed but MUST be stock replacement roof with stock appearing pillars (example performance bodies part #1015-81W). A 5” spoiler is allowed with a maximum 5” tall by 7” long sideboard. Stock appearing plastic nose and tail allowed but must match make of car/body. No fender flares allowed. The intent is for this to be a stock car class with as close to stock appearing bodies as possible. Stock bumpers or tube bumpers ok, must cut wrap around off the ends. No sharp edges. No bars connected to bumpers. No cow killer bumpers. All cars must have tow hook/chain on front and rear. Air Filter guards/deflectors are limited to 2" in length measured from front to back.
FRONT SUSPENSION:
All components and mounts must be steel, unaltered OEM, in OEM location and match frame. Rubber, nylon or steel lower A-frame bushings only - no offset or bearing type. No sway bars. Exceptions are: weight jacks allowed - must be in original centerline of spring tower; OEM upper A-frame mount may be moved or replaced with aftermarket steel non-adjustable mount matching upper A-frame bolt on design; OEM or OEM replacement ball joints allowed. For 1978-1987 GM mid-sized metric frame, OEM upper A-frame may be replaced using aftermarket upper A-frame. Shock location may be moved and may go through center of aftermarket upper A-frame, but frame cannot be altered in any way. Single hole shock mounts only. Tie rod adjusting sleeve may be replaced with swedge tube. No suspension stops of any kind allowed. Outboard shocks are allowed.
STEERING:
Steering must remain stock. Steering boxes must remain in stock location. Aftermarket steering wheel and quick release steering coupling are recommended. Quickeners or Quick steer boxes allowed.
SHOCKS:
One steel nonadjustable unaltered shock per wheel. All shocks must completely collapse at any time. No external or internal bumpers or stops. No coil over, air, or remote reservoir shocks. No Schrader or bladder type valve allowed. No coil over eliminators. One or all shocks may be claimed per event for $100 each, must finish on the lead lap, and must notify official within 15 minutes of race.
SPRINGS:
One steel spring per wheel only, or steel leaf spring if equipped OEM. Minimum 4.5 inches O.D., maximum 16 inch free height, non-progressive coil spring only. No spring rubbers allowed.
REAR END:
Quickchange, 9 inch Ford, or floater rear ends allowed. Steel tube rear ends or aluminum quick change axle housing may be used.
SUSPENSION
- American made OEM front frame clips only.
- No pick-ups or foreign car front clips allowed.
- Chevrolet engines must be in Chevrolet chassis.
- Ford and Mopar may use Chevy, Ford, or Mopar frames.
- Ajustable upper A-frames may be used.
- Lower A-frames must be stock. No IMCA extended type.
- Spindles must be steel.
- Stock type non-adjustable ball joints only.
- Any steel coil spring minimum of 4 inches in diameter allowed. One spring per wheel.
- No coil overs or coil spring eliminators allowed.
- Sway bars if used must be in stock locations.
- Weight jacks allowed on all 4 corners.
- Racing shocks allowed. One per wheel. MAY BE CLAIMED FOR $100.00 PER SHOCK BY ANYONE FINISHING ON THE LEAD LAP.
- No chassis adjustments allowed in drivers compartment other than a brake adjuster.
- There are 3 choices for rear suspension. -Three links may be used. Third link must not extend past back of roll cage behind driver. Third link must be solid. No springs or rubber biscuits allowed. Stock or aftermarket lower links may be used, but must be stock length. Panard or J-bars allowed. Leaf springs allowed. No fiberglass or monoleaf. No birdcages. Maximum 2 inch thick spacers. May use adjusters on rear of leaf springs. Factory 4 link must have all rear end mounts in stock location. On J-bar/Panard bar it must mount from left side of frame to right side of the third member or from the right side of frame to the left side of the third member.
- Once again all bars must be stock length (except 3rd link), lowers on lower, uppers on upper. All lower bars must be set at stock angles and the same angle. Upper bars on 4 link must be set at matching angles.
WEIGHT
Minimum weight, including driver, is 3000 pounds. 3050 with aluminum heads.
BRAKES
Must have 4 wheel brakes, option to run with 3 or 4
TIRES AND WHEELS
8 inch or 10 inch wheels. Used asphalt pull-offs. Steel wheels only. No bleeders allowed.
ENGINE
- Any automotive engine produced for use for passenger car use. Not to exceed 8 cylinders and no more than 2 valves per cylinder. May utilize LS series engines with carburetor.
- If you are running under 400 cubic inch motor, you can run a 4 barrell with a one inch spacer. If running over 400 cubic inch, you must run a 4412 2-barrell carburetor.
- Battery type ignition, no magnetos, MSD may be used, but swap rule with track will be in effect.
- Aluminum heads may be used but must add 50 pounds in front of motor plate.
- Left front spark plug must be plus or minus 1 inch from right front ball joint center line.
- The use of injection, super or turbo chargers, nitrous oxide, or water injection will not be allowed.
- No dry sump or external oil pumps.
SAFETY
See general rules.