2.6 SMOOTH BORE DIESEL 4X4

1. Driver must have a state issued drivers license. Vehicle must appear to be street legal, does not have to be licensed, inspected or insured for highway use. Driver must wear DOT helmet, long sleeve shirt and pants. Seat belt restraint must be used.

2. All “Operation Of Contest” rules apply.

3. All contestants at every event must sign a release & entry form, understanding that they are competing at their own risk and that they will not bring suit against any officials, volunteers, Promoter and/or property owner. By signing the release & entry forms you agree to all rules set forth and warrant that your vehicle meets all the requirements for this class.

4.Maximum truck weight including driver is 8,000lbs. Hanging front weights are allowed, may not extend more than 60 inches forward of the centerline of the front axle. No weights allowed in cab, any weights in the bed must be securely mounted. All trucks must be weighed before the class begins.

5. O.E.M. Chassis is mandatory. The vehicle must retain the full O.E.M. Chassis. Wheel tubs, back half conversions and tube chassis are prohibited. Lengthening of the frame allowed up to 158 inches. Longer trucks (158” - 172”) must maintain O.E.M. Measurements for body being used.

6. The body must be O.E.M. Truck body including full bed floor. No flat beds permitted. The body must retain the full sheet metal. Aftermarket hoods permitted. The hood must be closed and securely latched when hooked to sled. All window glass must be in place.

7. Maximum cubic inch 460. Engine must be in O.E.M. Locations for the body used. No aftermarket blocks permitted. Engine must have 3/8 cable surrounds #1 & #2 cylinders and must pass thru the manifolds. 2 clamps at splice with 4-6 inches of slack.

8. Cylinder head must be O.E.M. Or O.E.M. Replica for brand of engine. Outside dimensions of cylinder head must measure factory width and length. No billet heads of any material. Head must retain OEM valve angle. No deck plates permitted. Side draft and aftermarket intake manifolds are allowed. Air to air intercooler only.

9. Turbo is limited to a 2.600 inch inducer bore. Bore must be smooth. NO Map Width Enhancement groove (MWE) allowed. Compressor wheel must protrude into 2.600 bore for 1/8 inch. Bore will be checked with a 2.605” turbo plug. Plug must not be able to enter inducer bore and contact wheel. Turbocharger inlet hose must be removed for measuring at any time requested by Tech Official or vehicle will be disqualified.

10.All vehicles must be equipped with upward pointing exhaust located either directly behind cab or out of the truck hood. Two 3/8” diameter bolts must be placed through exhaust pipe in a cross pattern within one inch of each other and within 12” of turbo.

11. Maximum of one P Pump up to P7100 allowed. 13MM plunger limit. Ag governors permitted. The use of multiple high pressure common rail fuel pumps is legal.

12. Hook point to be no closer than 44 inches to centerline of rear axle. Maximum hitch height of 24 inches with a minimum 3.75” x 3” opening for sled hook. Hitch must be stationary in all directions and must be frame mounted. All hitch parts must be centerline of rear axle or behind. Hitch must not exceed 25 degree angle from pivot point to hook point. No hitch support adjusters fastened to rear axle housing shall be above center point of rear axle. Pivot pin of draw bar can be no further forward than the centerline of rear axle. Hitch may be “receiver” style hitch.

13. Tire must be D.O.T. Approved with maximum size of 35x12.50. No studded tires or chains. No alterations to tires permitted. No bar or Terra tires. Dual wheels are prohibited.

14. Vehicles must have O.E.M. Firewall and floor. Only holes allowed are those for brakes, clutch, transmission controls and wiring. Hand throttles are allowed, return springs are required. 2.5lb, fire extinguisher must be securely mounted within reach of driver.

15. Truck, chassis and driveline being used (including front and rear axle, transmission, transfer case) must have been originally produced for diesel engine 1 tom or smaller pick up truck.

16. Minimum wheelbase is 130 inches. Converted gas engine short wheelbase trucks are not permitted.

17. Suspension: The upper mounting point for strut assembly must be in factory location. Adjustable caster/camber pillow ball mounts are permitted. The lower control arm may be strengthened provided the factory mounting points are maintained. Strut tower braces, lower tie bars, sway bars and limit straps are permitted. Traction bars and devices are permitted. Raising or lowering of vehicle height with suspension modifications is permitted but must be bolt on only. Weld permitted for attachment to frame and axle only. Blocked suspension permitted. No air bags. Rear suspension may be made solid. Must have 4 wheel hydraulic brake system in good working condition.

18. Safety switch (rain cap or guillotine) must shut off air to diesel engines. Switch will be securely mounted to back of truck. A 2 inch or bigger solid ring must be attached to end of switch. Ring must be zip tied to switch bracket. Switch must also be able to be activated in cab while driver is secured in vehicle.

19. Axle shields are required. Shield to be .060” thickness steel or aluminum. A hole may be cut in 1 shield to allow operation of hub lock.

20. All trucks in this class must have U-joint shields on all driveshaft U-joints visible from side of truck. Shield must be minimum 6 inches wide, made of minimum 3/16 inch steel or ¼ inch aluminum and centered over U-joint. All driveshafts must have driveshaft loops 12 inches from each u-joint, minimum 1 inch wide steel or solid ½ inch rod, 360 degrees around driveshaft. Driveshaft loops and U-joint shields may be 2 pieces bolted together to form loop. No chains allowed. All shields and loops must be securely mounted to the vehicle.

21. SFI bell housing and SFI automatic transmission blankets or shields are required on any vehicle running 4500 rpm or higher. Manual transmission vehicles with engine running 4500 rpm or higher must have clutch meeting SFI Spec1.1 or 1.2 and SFI Spec 4.1 flywheel shield or blanket properly attached to engine block extending rearward to overlap the transmission. Any automatic transmission equipped vehicle with engine running 4500 or higher must be equipped with a SFI Spec 29.1 flex plate and flex plate shield meeting SFI Spec 30.1

22. All engines running 4500 rpm or higher must be equipped with a harmonic balancer or damper meeting SFI Spec 18.1

23. Radiator must be in original location. All engine fans must be O.E.M. Shrouded.

24. Fuel must be #1 or #2 diesel fuel only. Soy/Biodiesel fuel is permitted. No other combustible material (nitrous, propane, etc) may be injected into the turbocharger or any part of the air intake system. Water injection is prohibited. All water injection, nitrous & propane systems must be removed from vehicle. Air to air intercooler only.

25. Track officials will have the option to check competitors for rule violations at any time during the events. Contest will be governed by Track Officials and Competition Director with all decision final!

26. Verbal or physical abuse toward any track official will result in automatic disqualification.