2008 4-Cylinder Pure Stock Rules (In PDF)

 2007 Rules and Regulations

Safety Rules

1. ALL DRIVERS ARE REQUIRED TO HAVE THE FOLLOWING IN USE EVERY TIME THEY ARE IN THEIR CAR ON THE TRACK:
   1. Snell 2005 SA approved full face helmet.
   2. Driver must have proper eye protection.
   3. Fire retardant drivers suit, socks, shoes, and full coverage gloves.
   4. Fire retardant neck brace.
      
      ADVISED but not mandatory: Top and bottom fire retardant underwear, and/or; a double layer fire retardant driver’s suit. Also, helmets with fire retardant interior. Helmets should be inspected and/or replaced periodically.
2. A 3” lap and shoulder harness (less than 3 years old) with sub belt is required. Belts must be attached to car in a safe manner as approved by technical inspector.
3. Arm restraints are required.
4. Each pit will have an adequate fire extinguisher. Fire extinguisher will be in full view at racetrack, at rear of trailer.
5. Kill switch is required to be within the drivers reach with arm restraints on.
6. Technical inspector reserves the right to disqualify any car judged to be unsafe until corrections are completed.

Engine Specs

1. Only reciprocating piston engines are allowed. No fuel injection (except OEM stock on motorcycle engines), turbo charging, super charging or rotary engines allowed. Engines will only be legal if at least 300 engines of identical design and assembly have been manufactured and made available for sale. No prototype or experimental engines allowed.
2. Any production 4 cycle air or liquid cooled engine with a maximum of 4 cylinders is allowed; limited to the use of only one engine. Original engine displacement must not exceed 750cc. 1 mm maximum overbore is allowed to repair damaged cylinders. 2004 and newer liquid cooled EFI engines are allowed, timing and exhaust modifications only.
3. Any production 2-cycle air or liquid cooled case or cylinder reed engines with a maximum of two cylinders/600cc. No overbore is allowed for damaged cylinders. Original engine displacement of 600cc. Triples will be allowed 1 mm overbore. 3 cylinder non case or cylinder reed (piston port) engines up to 600cc are allowed.
4. All cars must have exhaust silencers at the start of every race. Silencers must direct noise down & towards rear of the car.

Carburetion

1. Carburetor boring is allowed to a maximum size of 40.5 mm. at spigot end of carburetor (engine side). Carburetor must fit stock 38 mm. boot. No oval boring.
2. No fuel injection permitted on snowmobile engines. OEM stock fuel injection allowed on motorcycle engines only.
3. No auxiliary injection systems permitted. Nitrous oxide, air, water, etc.
4. No turbo or supercharger systems permitted.
5. Gasoline, gasohol, aviation gas, race gas, octane boosters, and alcohol (methanol, ethanol) are allowed. Nitrous oxide, nitro-methane, and oxygen bearing fuel additives are prohibited.

Chassis Specifications

1. Cars must have sprung suspension at all four wheels with with solid axles. No independent suspensions.
2. Cars must be of an open wheel and open cockpit design.
3. To improve the appearance and increase the appeal of Mini- Sprints, cars must have a good hood and tail. Cars must be painted and neat appearing at all times. They should resemble an upright sprint car.
4. All cars must be clearly identified by good sized numbers on both sides. If space permits 15”- 16” high.
5. All cars must have a floor pan extending from the front of the vehicle or firewall to the front of the driver’s seat, also a metal firewall completely separating the driver from the engine.
6. A quick release steering wheel must be used.
7. All cars must have a workable on/off, or kill switch, which must also control the electric fuel pump shut off. Switch must be mounted on the dash area and easily seen and accessible.
8. The brakes must be in good working order at all times, the minimum requirement is one rear wheel hydraulic brake capable of locking up both rear wheels.
9. Chain must be guarded properly. Must completely cover chain if inside frame rails, to protect driver and fuel tank.
10. Clutches and belt should be guarded properly on the snowmobile engine powered cars.
11. Fuel tanks must be well secured and are not to exceed 2 ½ gallons in capacity. They should be foam filled. Larger, safety approved fuel cells are allowed. Pressurized fuel tanks are prohibited. Manuel, electric, and pulse fuel pumps are permitted, providing that they are mounted securely outside the driver’s compartment. A fuel shut-off valve in the cockpit area that is within easy reach of the driver with seat belts and arm restraints fastened is recommended.
12. All batteries must be mounted securely to the chassis. Rope and/or rubber cords are not considered approved fasteners. vent hoses must extend to the bottom of the chassis.
13. Liquid cooled cars must have overflow hoses extending to the bottom of the chassis. If an overflow bottle is used, it must be made of plastic and must be securely fastened to the chassis outside of the driver’s compartment.
14. Radiators or oil coolers may not be mounted on roll cage above driver’s head or in driver’s compartment.
15. Top wing is required at the beginning of each race. Wings must be well constructed and cannot extend beyond the outside edge of the tires. Plywood wings are not allowed. They should be made of aluminum. Only one top wing and one nose wing are allowed of single element design. Top area dimensions are not to exceed 16 square feet for the top wing and 3 square feet for the nose wing. The sideboards are not to obstruct driver’s vision. Wing sliders are allowed.
16. Wheelbase: Minimum: 54” to a maximum of 75”.
17. Track width: Minimum: 40” to a maximum of 54” (center of tread).
18. It is recommended that the chassis tubing be a minimum strength of 1010 DOM (Drawn Over Mandrel) .095” wall thickness seamless mild steel or 4130N .083” wall thick chrome moly.
19. The roll cage must be a minimum of 1.250” diameter .083” wall thickness steel round tubing.
20. Primary or major frame members (upper and lower frame rails) must be a minimum of 1” diameter x .083” wall thick- ness steel tubing.
21. Secondary or minor frame members (cross bracing, etc.) must be a minimum of .750” x .083” wall thickness steel tubing.
22. An inspection hole of 1/8” - 3/16” is to be drilled in the roll cage to facilitate inspection if necessary.
23. All cars must have nerf bars on both sides and bumpers on the front and rear. It is recommended that they be a minimum of .750” diameter x .083” wall thickness round tubing. Nerf bars must extend to within 2”, but not past the outside edge of the rear tires. Nerf bars and bumpers must be mounted securely to the chassis.
24. All cars must weigh a minimum of 800 lbs. with driver after every race. Ballast weights must be painted white and be securely bolted to the frame. Top 5 must scale.

Tires & Wheels

1. Rims – Maximum of diameter of 13” and a maximum width of 10”.
2. Tires – Racing tires of 13” with open outside diameter, width and durometer.

General Rules

1. Drivers should always show good sportsmanship at the race track.
2. There should be no intentional hitting, bumping, or blocking of other cars.
3. Rookie drivers should start at the back of the pack for at least their first race date.
4. Cars being lapped should try to hold their line when shown the blue with yellow diagonal stripe move over flag.
5. Drivers, watch for the flags and lights!