Pure Stock Rules
Updated 02/13/2022
RULE BOOK DISCLAIMER:
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.
IF IT DOESN’T SAY YOU CAN, THEN YOU CAN’T!
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BODY:Any American made stock passenger car body on a stock unaltered full frame, or unibodies. Stock appearing aftermarket plastic nose or tail pieces are allowed. Rear of car must be sealed off, no exposed fuel cell. No spoilers (even if factory equipped), wings, skirts, air scoops, hood scoops, or anything that alters stock appearance. Bodies cannot be moved from the original body mount rubber bushing no more than +/- 1” cannot be less than 5 ½” from ground. A front visor is allowed on the windshield area MAX 7 inches. No side or rear window visors allowed. Sunroofs and T-tops must be reinforced and enclosed. No nerf bars. Maximum one inch wide by two inch tall steel or lexan rub rails allowed - bolted flush to body. All glass, plastic, upholstery, lights, mirrors, and trim must be removed. Cars must be stock appearing. No cutting, channeling, shortening, or modifying of body is allowed. No excessive trimming of fenders or hoods allowed, must maintain stock OEM appearance. All doors, fenders, and window openings must remain stock appearing and OEM dimensions and should be the same on both sides. No straight slab sides. No enclosed interiors or decking allowed. Front edge of rear deck cannot be more than 8” forward of center of rear-end and must have at least 2” continuous drop from front to rear. Rear of dash can be no more than 35” from the center of the distributor or 28” from back edge of the center of stock hood. Front and rear firewalls must remain in stock location and be full and complete. Cars must have a complete stock steel roof mounted in OEM location and OEM rake and angle for model. All openings should be covered as to isolate the driver, subject to track approval. Racecar body should be maintained in such a manner as to keep a presentable appearance.
Cars without stock steel front fenders will have 20lb weight penalty in front of engine. Cars without stock steel hood will have 10lb weight penalty in front of engine. Cars without stock OEM windshield posts attached to firewall must add 20lbs. in front of the engine total of 50 for all three, must be lead ballast.
BUMPERS: Stock type rear bumper required, a fabricated front bumper may be used with the following conditions: cars with aftermarket nose pieces- the bumper may extend past frame rails for support and reinforcement. Must be behind nosepieces. Cars without nosepieces- the bumper may not extend past front frame horns. NO SHARP EDGES.
ROLL CAGE: Minimum four-point cage, minimum size 1 ½ “O. D. by .095” wall thickness. Minimum three bars in driver’s side door, and two bars on passenger side door (three bars if passenger in car). Four-point quick release seat belt and harness required for driver and passenger. Racing seats required. Must have window nets and fire suit for driver and passenger. Must have at least three bars in front of driver and passenger in windshield area.
ENGINE: Must be stock for the make and model except no 400’s or larger small or big blocks. Chevy must use 4 equal valve relief pistons. OEM crankshaft only- cannot be lightened. No aerowing, bullnose, knife edge, undercut or drilling of second or third rod throws. OEM steel Connecting rods only must remain stock OEM length, weight and shape. No lightening of any parts. Aftermarket water pump, mini starter, pulleys, harmonic balancer and oil pans okay. Aftermarket power-steering pumps okay. Metric cars may run a 350. NO stroking or de-stroking. Engine must be in stock location. Solid motor and transmission mounts okay. Maximum cranking compression 175lbs. (ignition off, engine turned over 5 times). Oil pans must have at least 1”inspection hole. All Fuel Pumps must fit in front of the crossmember.
CAMSHAFT, VALVETRAIN, AND CYLINDER HEADS: Hydraulic cam and flat tappet lifters only. .400 maximum lift. Must maintain 14” of vacuum at 1200 rpm. 1.94 maximum intake valve diameter, 1.50 maximum exhaust valve diameter on Chevrolet engines. No hollow valve stems. Stock size and shape valve springs and retainers. Stock length and diameter pushrods only. Stamped steel 1.5 rockers on Chevy, 1.6 on Ford and Chrysler, NO roller tips. Open chambered heads only, must be unaltered, O.E.M. NO porting, polishing, or gasket matching allowed. The only GM head numbers allowed are 14079267, 3986336, 3986339, 3986339X, 3986388, 3932441, 376445, 3928454, 3932454, 3876487, 3973487, 3973487X, 3973493, 3951598, 468642, 330862, 333882, 3998920, 3998991, 3998993, 3998997, and 3970126. Screw in studs and guide plates ok. 305 engines may use 305 heads (no vortec).
CARBURATION AND FUEL SYSTEM: Cast Holley 4412 -2 barrel only. Must be unaltered. Choke plate may be removed. 4412 must be cast into choke horn of carb. Maximum spacer and adapter 1” combined total. Fuel pump must be in stock location for make, NO electric pumps. Fuel injection is allowed with totally stock engine. No High Performance. Must have working emergency kill switch.
EXHAUST: Stock unaltered cast iron exhaust manifolds only no porting or grinding allowed. No Chevy center dump, Corvette, marine, Lt1 or tubular steel type manifolds. No adaptors between head and manifold must be able to use all OEM exhaust bolt holes in head. No two into one exhaust or x pipes must remain duals.
INTAKE MANIFOLD: Stock OEM unaltered aluminum or cast iron intake only. No aftermarket or stock high performance or high rise. No bowties. No porting, polishing, cutting or gasket matching.
TRANSMISSIONS: Any stock type automatic or manual. Automatics must have stock appearing working 10” torque converter cannot be smaller with ring around it. No direct drives. Transmission Cooler ok. Manual must have single disc 10.5” clutch, flywheel and pressure plate must be steel minimum 16lb steel flywheel. No mini clutches. Steel drive shafts only must be painted white and have a loop 6” from front u-joint.
FUEL: Pump or racing gas only. No additives or smells. Fuel cell must be secured in trunk any part of fuel cell cannot be forward of any part of rear end.
SUSPENSION: Front and rear suspension must be stock unaltered OEM for that make and model of frame, ball joints, spindles and all components. No air shocks. No alterations to any part of the suspension or frame will be allowed. Any spring in stock location no spring rubbers, no adjustable weight jacks of any kind, must sit in unaltered stock mounts. May run IMCA type upper control arms. Sway bars must be stock for make and model mounted in OEM mounts. No adjustable suspension stops of any kind. Shocks must have stock type rubber ends, no screw on type rod ends even if welded, must be mounted in stock location on frame, control arm and rear-end. No bulb-type, threaded body, coil-over, or remote reservoir shocks. No external or internal bumpers or stops no Schrader valves on shocks.
REAR END: Stock rear-end for make and model no modifying axle bearings or length. All brackets and control arm, shock mounts must be in stock location. Gears may be locked must use stock unaltered ring gear carrier may weld or use bolt in locking blocks. No full spools, Detroit lockers or torque sensing devises. Full floater axle is ok, no gun drilled axel.
STEERING / DRIVER SEAT: Steering boxes must remain in stock location. Aftermarket steering wheel and quick release steering coupling are recommended. Quick steer boxes allowed. NO part of driver seat may be no further back than 25” forward of center line of rear end housing.
RADIATORS: Any (1) radiator that fits in original location without any body modifications is allowed.
IGNITION: One 12 volt battery only must be mounted securely in rear of driver’s compartment or trunk area. One stock type distributor, module and coil in stock location only. Ignitions on/off switch must be clearly marked. No traction control devices of any kind. No digital gauges or tachs.
BRAKES: May use any (1) one master cylinder. Aftermarket pedal OK. Must have at least 3 working brakes. Right front may be blocked. No bias adjustment is allowed. Disc brakes allowed in rear No aluminum or composite rotors or calipers. Must use steel stock type rotors on rear disc. No lightening of components. Master Cylinder must be on the firewall.
TIRES AND WHEELS: 10” maximum wide wheels allowed, 15” diameter steel wheels only, wheel covers and mud plugs right side only. Bead locks or screws allowed on the right side only. NO bleed-off valves. Must run 1” steel lug nuts. Approved asphalt pull-offs only, must durometer 60 or higher. No grooving or softening allowed. May run USED KK704's or USED G60's.
WEIGHT: Weight may be securely added in trunk or under the hood, but not in plain view or within the driver’s compartment must be painted white with car number. Car must weigh minimum 3200 lbs. with driver after race.
COURTESY RULE: Any car with “minor” rule infractions will be allowed to race (1) event. Must be determined before the race. Cars with infractions are subject to weight penalty.
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.
IF IT DOESN’T SAY YOU CAN, THEN YOU CAN’T!
----------------------------
BODY:Any American made stock passenger car body on a stock unaltered full frame, or unibodies. Stock appearing aftermarket plastic nose or tail pieces are allowed. Rear of car must be sealed off, no exposed fuel cell. No spoilers (even if factory equipped), wings, skirts, air scoops, hood scoops, or anything that alters stock appearance. Bodies cannot be moved from the original body mount rubber bushing no more than +/- 1” cannot be less than 5 ½” from ground. A front visor is allowed on the windshield area MAX 7 inches. No side or rear window visors allowed. Sunroofs and T-tops must be reinforced and enclosed. No nerf bars. Maximum one inch wide by two inch tall steel or lexan rub rails allowed - bolted flush to body. All glass, plastic, upholstery, lights, mirrors, and trim must be removed. Cars must be stock appearing. No cutting, channeling, shortening, or modifying of body is allowed. No excessive trimming of fenders or hoods allowed, must maintain stock OEM appearance. All doors, fenders, and window openings must remain stock appearing and OEM dimensions and should be the same on both sides. No straight slab sides. No enclosed interiors or decking allowed. Front edge of rear deck cannot be more than 8” forward of center of rear-end and must have at least 2” continuous drop from front to rear. Rear of dash can be no more than 35” from the center of the distributor or 28” from back edge of the center of stock hood. Front and rear firewalls must remain in stock location and be full and complete. Cars must have a complete stock steel roof mounted in OEM location and OEM rake and angle for model. All openings should be covered as to isolate the driver, subject to track approval. Racecar body should be maintained in such a manner as to keep a presentable appearance.
Cars without stock steel front fenders will have 20lb weight penalty in front of engine. Cars without stock steel hood will have 10lb weight penalty in front of engine. Cars without stock OEM windshield posts attached to firewall must add 20lbs. in front of the engine total of 50 for all three, must be lead ballast.
BUMPERS: Stock type rear bumper required, a fabricated front bumper may be used with the following conditions: cars with aftermarket nose pieces- the bumper may extend past frame rails for support and reinforcement. Must be behind nosepieces. Cars without nosepieces- the bumper may not extend past front frame horns. NO SHARP EDGES.
ROLL CAGE: Minimum four-point cage, minimum size 1 ½ “O. D. by .095” wall thickness. Minimum three bars in driver’s side door, and two bars on passenger side door (three bars if passenger in car). Four-point quick release seat belt and harness required for driver and passenger. Racing seats required. Must have window nets and fire suit for driver and passenger. Must have at least three bars in front of driver and passenger in windshield area.
ENGINE: Must be stock for the make and model except no 400’s or larger small or big blocks. Chevy must use 4 equal valve relief pistons. OEM crankshaft only- cannot be lightened. No aerowing, bullnose, knife edge, undercut or drilling of second or third rod throws. OEM steel Connecting rods only must remain stock OEM length, weight and shape. No lightening of any parts. Aftermarket water pump, mini starter, pulleys, harmonic balancer and oil pans okay. Aftermarket power-steering pumps okay. Metric cars may run a 350. NO stroking or de-stroking. Engine must be in stock location. Solid motor and transmission mounts okay. Maximum cranking compression 175lbs. (ignition off, engine turned over 5 times). Oil pans must have at least 1”inspection hole. All Fuel Pumps must fit in front of the crossmember.
CAMSHAFT, VALVETRAIN, AND CYLINDER HEADS: Hydraulic cam and flat tappet lifters only. .400 maximum lift. Must maintain 14” of vacuum at 1200 rpm. 1.94 maximum intake valve diameter, 1.50 maximum exhaust valve diameter on Chevrolet engines. No hollow valve stems. Stock size and shape valve springs and retainers. Stock length and diameter pushrods only. Stamped steel 1.5 rockers on Chevy, 1.6 on Ford and Chrysler, NO roller tips. Open chambered heads only, must be unaltered, O.E.M. NO porting, polishing, or gasket matching allowed. The only GM head numbers allowed are 14079267, 3986336, 3986339, 3986339X, 3986388, 3932441, 376445, 3928454, 3932454, 3876487, 3973487, 3973487X, 3973493, 3951598, 468642, 330862, 333882, 3998920, 3998991, 3998993, 3998997, and 3970126. Screw in studs and guide plates ok. 305 engines may use 305 heads (no vortec).
CARBURATION AND FUEL SYSTEM: Cast Holley 4412 -2 barrel only. Must be unaltered. Choke plate may be removed. 4412 must be cast into choke horn of carb. Maximum spacer and adapter 1” combined total. Fuel pump must be in stock location for make, NO electric pumps. Fuel injection is allowed with totally stock engine. No High Performance. Must have working emergency kill switch.
EXHAUST: Stock unaltered cast iron exhaust manifolds only no porting or grinding allowed. No Chevy center dump, Corvette, marine, Lt1 or tubular steel type manifolds. No adaptors between head and manifold must be able to use all OEM exhaust bolt holes in head. No two into one exhaust or x pipes must remain duals.
INTAKE MANIFOLD: Stock OEM unaltered aluminum or cast iron intake only. No aftermarket or stock high performance or high rise. No bowties. No porting, polishing, cutting or gasket matching.
TRANSMISSIONS: Any stock type automatic or manual. Automatics must have stock appearing working 10” torque converter cannot be smaller with ring around it. No direct drives. Transmission Cooler ok. Manual must have single disc 10.5” clutch, flywheel and pressure plate must be steel minimum 16lb steel flywheel. No mini clutches. Steel drive shafts only must be painted white and have a loop 6” from front u-joint.
FUEL: Pump or racing gas only. No additives or smells. Fuel cell must be secured in trunk any part of fuel cell cannot be forward of any part of rear end.
SUSPENSION: Front and rear suspension must be stock unaltered OEM for that make and model of frame, ball joints, spindles and all components. No air shocks. No alterations to any part of the suspension or frame will be allowed. Any spring in stock location no spring rubbers, no adjustable weight jacks of any kind, must sit in unaltered stock mounts. May run IMCA type upper control arms. Sway bars must be stock for make and model mounted in OEM mounts. No adjustable suspension stops of any kind. Shocks must have stock type rubber ends, no screw on type rod ends even if welded, must be mounted in stock location on frame, control arm and rear-end. No bulb-type, threaded body, coil-over, or remote reservoir shocks. No external or internal bumpers or stops no Schrader valves on shocks.
REAR END: Stock rear-end for make and model no modifying axle bearings or length. All brackets and control arm, shock mounts must be in stock location. Gears may be locked must use stock unaltered ring gear carrier may weld or use bolt in locking blocks. No full spools, Detroit lockers or torque sensing devises. Full floater axle is ok, no gun drilled axel.
STEERING / DRIVER SEAT: Steering boxes must remain in stock location. Aftermarket steering wheel and quick release steering coupling are recommended. Quick steer boxes allowed. NO part of driver seat may be no further back than 25” forward of center line of rear end housing.
RADIATORS: Any (1) radiator that fits in original location without any body modifications is allowed.
IGNITION: One 12 volt battery only must be mounted securely in rear of driver’s compartment or trunk area. One stock type distributor, module and coil in stock location only. Ignitions on/off switch must be clearly marked. No traction control devices of any kind. No digital gauges or tachs.
BRAKES: May use any (1) one master cylinder. Aftermarket pedal OK. Must have at least 3 working brakes. Right front may be blocked. No bias adjustment is allowed. Disc brakes allowed in rear No aluminum or composite rotors or calipers. Must use steel stock type rotors on rear disc. No lightening of components. Master Cylinder must be on the firewall.
TIRES AND WHEELS: 10” maximum wide wheels allowed, 15” diameter steel wheels only, wheel covers and mud plugs right side only. Bead locks or screws allowed on the right side only. NO bleed-off valves. Must run 1” steel lug nuts. Approved asphalt pull-offs only, must durometer 60 or higher. No grooving or softening allowed. May run USED KK704's or USED G60's.
WEIGHT: Weight may be securely added in trunk or under the hood, but not in plain view or within the driver’s compartment must be painted white with car number. Car must weigh minimum 3200 lbs. with driver after race.
COURTESY RULE: Any car with “minor” rule infractions will be allowed to race (1) event. Must be determined before the race. Cars with infractions are subject to weight penalty.
