PRO STOCK 4 RULES
1.) Rear wheel drive only. Max wheel base 104”.
2.) Stock firewall and floor pan in stock location. Or steel in stock location replaced for repairs.
3.) Stock bodies, aftermarket bodies and noses are permitted. Must be stock in appearance and track approved. May use a stock tail piece or 12” tall aluminum to close in the rear. 6” spoilers are permitted.
4.) Three bars in front of the driver or screen to protect the driver from debris.
5.) OEM transmission with all gears in working order.
6.) Stock or stock replacement clutch and pressure plate. Stock flywheel, must weigh 16 lbs. No scalloped flywheels.
7.) Full roll cage 1 ½” x .095 steel. 8 Anchor points recommended and must be secured to uni-body. Must be track approved.
8.) 4 driver door bars, at least 3 bars in the right side door, all major stress points are to have gussets.
9.) Stock chassis may tie chassis together. Engine must mount in stock location with no setback.
10.) Brakes may have racing pedals with any master cylinder. No adjustments with all four wheels to have working brakes. No drilled rotors or lightened drums.
11.) Can run a right front brake shut off as long as all components are on the car.
12.) Stock struts and any steel non-adjustable shocks allowed. Caster and camber plated allowed, no screw jacks. Adjustable cups and shackles allowed. Factory pan hard bars only. Top shock mounting point may be relocated.
13.) Drive shaft 1/ ½” OD minimum. Steel only. Must be painted white.
14.) Rear-end must be stock up to a 9” for the car. No lightening allowed. May use a mini spool or weld rear-end. Axels must be stock.
15.) Stock steering components. Steering quickeners allowed.
16.) Any steel wheels, 7” – 8”. No mix and match. Large wheels allowed. Bead locks allowed on the right side. Any 60 or 70 series DOT street tire 13”, 14”, or 15” untouched. No racing tires of any type. No American Racers or Hoosiers. No soaking, grooving, or siping. Must punch 60. May run Towel City Retread Mini Stock/Legend DOT stamped 205/60/13 (89 compound).
17.) Mufflers are mandatory
18.) Toyotas may run front struts coilover kit
** Pro Stock // Safety rules**
1.) Window nets are mandatory. Sprint-style window nets will not be permitted. Good quality full face racing helmets or DOT approved helmets are required.
2.) Minimum single-layer fire suit required. (SA 3.2A specification recommended)
3.) Fire proof gloves are strongly recommended. (SFI 3.3 specification recommended)
4.) A 4 or 5 point harness, properly mounted per manufacturers’ specifications, is required.
5.) Belts must have been manufactured in the last 5 years. Any worn, abraded or torn belts must be replaced.
6.) A 5 lb. (or greater) fire extinguisher should be securely mounted within the drivers’ reach.
7.) Only racing-type seats, properly mounted per manufacturers’ specifications, are allowed.
8.) A head-and-neck restraint system is mandatory (SFI 16.1 compliant recommended).
9.) A firewall must be in place between the driver compartment and fuel cells, fuel lines, or tanks.
10.) Safety chains must remain securely fastened on the front and rear of the racecar at all times.
11.) Any time a car is on the track all safety gear is required.
12.) Must have a fire extinguisher and seat belts that are up to date. Fire suppression is recommended.
13.) Anytime a car is on the track all safety gear is required.
14.) Race receivers are mandatory.
15.) No radios allowed.
24.) Fire extinguisher in car is mandatory
25.) Any time a car is on the track all safety gear is required.
** Pro Stock 4 // Engine Rules **
1.) 1 lb. per c.c. as measured. Minimum weight 2000 lbs. after the race with the driver. Weight must be marked on the hood or front fender near the driver.
2.) 4-cylinder OEM block only. Wear tolerance will be allowed.
3.) OEM intakes only.
4.) Stock cast iron manifolds or header with $150 claim rule. No TRI-Y’s.
5.) Stock crank, stock stroke, no lightening. Any steel rods allowed.
6.) Any flat top pistons. Toyota: 3TC may run dome .267, 20, and 22 may run dome .125. Zero deck height.
7.) Stock 4-cylinder carburetor for make of car or Holley 350 CFM (#7448) must have an air horn with a number. 1” thick maximum adapters allowed with 2 gaskets only @ .070” max or 1 stock gasket without adapter. Holley 350 CFM Venturi and base measurements must remain factory.
8.) Max cam lift 425”, no rollers checked with .025” lash (hydraulic or solid allowed). 350 Carb allowed.
9.) OEM oil pumps only.
10.) Steel valves only, no hollow valves, stock diameter. Single or double steel springs allowed.
11.) Any steel retainers allowed.
12.) Ignition must be stock type distributor and coil. May use Mel’s Ignition. No aftermarket multiple spark or adjustable electronic type systems allowed.
13.) No traction control allowed.
14.) Head must be stock OEM, absolutely no poring or polishing allowed. No extrude honing allowed. No acid porting allowed. Ports must remain at factory OEM shape and volume. Head may be angle cut. A bowl cut is allowed but cannot exceed the ID of the valve seat and can be no deeper than the valve guide. Bowl cut must be concentric with the valve guide.
15.) Card baseplate unmodified. Stock metering block
16.) Butterfly screws unaltered. Holes in butterflys are okay.
Safety chains must remain securely fastened on the front and rear of the car at all times or you will be immediately disqualified.
Competitors must present cars for inspection prior to participating in any racing event. A pre-race inspection will be made ONLY to ensure safety protocols have been adhered to. Questions of legality can and will be answered during the pre-race inspection if asked by an entrant. No guarantee of legality shall be expressed or implied during pre-race inspection. Legality will be determined in post-race inspection. Fairgrounds Raceway has final ruling on all questions of legality.
Fairgrounds Raceway officials have every right to change the rules if deemed necessary at any point during the season. Officials may be open to changing rules if it is best for the majority of the class.
Ⓒ 2024 Fairgrounds Raceway
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