Two-Wheel Drive Trucks – NTPA Rules Book with No Variances
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Open Four Wheel Drive Trucks
Blower Trucks – Blower Overdrive Unlimited; Hitch 30% of Wheelbase; 26 Inch Height; 6200 Lbs.
Modified Trucks – Hitch 30% of Wheelbase; 26 Inch Height; 6500 Lbs.
Diesel Trucks – Refer to NTPA Rulebook on Wheelbase – Hitch – Weight
Four Wheel Drive Trucks
Blower Trucks run 36% on hitch 6200 Lbs. on weight and 30% on blowers
Modified Trucks run 30% on hitch, 6200 Lbs. on Weight and 750 Cubic inch on Engine
Pro-Stock Four Wheel Drive Trucks
- Pro Stock 4WD trucks shall follow current NTPA Rule Book for Modified Four Wheel Drive except where superseded by rules found herein.
- Any truck body, any factory frame.
- Carburetor must have a stock 4500 base plate. No stretched carburetor. No tunnel ram or sheet metal intakes. No billet intakes or billet carburetors.
- Engine & Head Specifications:
- Maximum 485 cubic inch. Any GM style block must be 4.84 bore spacing. Any Dodge style block must be 4.8 bore spacing. Any Ford style block must be 4.9 bore spacing. No JC50, JC51, DRCE3, or aluminum blocks. Engine can be no further forward than 12 inches from front of block saver plate to center of front axle housing.
- GM may run any conventional port designed head. Ford may run an “A” style head only. Dodge may run B1 head only.
- Conventional port designed head is classified as a head with the port spacing that must be left to right. No spread port, billet, or conventional spread port heads allowed.
- Headers and open exhaust allowed, must exit through hood or down and back.
- Body Specifications:
- Factory wheelbase may be shortened or lengthened to maximum 134 inches. Bedside may be altered in front of wheel wells to match wheelbase on all trucks.
- Rear wheel width cannot be narrower than 34 inches from inside bead to inside bead of rear wheels.
- OEM fiberglass components only. Front clip of truck (firewall forward only) can be fiberglass.
- No working hydraulic stops on front suspension during pull. Must have quick disconnect and shall not be touching spring or axle housing before, during, or after pull. Weight boxes must stay stationary before crossing the scales and cannot be moved until after the pull is over. Any air pressure adjustment requires a re-measurement of hitch height.
- Any street legal tire may be run measuring up to or less than 33 inches in measured height. Terra and Cepek tires allowed along with any bar tire up to 31×15.50×15. No recapped tires allowed. Must have size on sidewall by manufacturer.
- Any transmission, transfer case, front end, or rear end allowed. No planetaries.
- Hitch Specifications:
- Hooking point has to be horizontal on hitch.
- Drawbar will be 26 inches, 36% of wheelbase length. No drawbar greater than the angle of the sled chain (acceptable angle 0 degrees to a maximum of 33 degrees). The drawbar adjusters cannot attach to anything above centerline of the rear axle. The adjusters can only go downward.
- Acceptable fuels are race gas or alcohol. No oxygenated fuels, oxygen carriers, or combustion accelerators.
- 1% tolerance on engine measurements.
Light Limited Super Stock Tractors
6000 LB LIGHT LIMITED SUPER STOCK TRACTOR
This class will run under NTPA “Super Stock Rules” including shielding, safety, and SFI requirements, plus the following:
- Cubic inch
- Diesel Engine- 470
- Alcohol Engine-370
- A 1% tolerance will be given on cubic inch limitations to allow for normal engine wear.
- No V-8 engines permitted
- OEM cylinder heads only, cylinder head must match block – valves cannot seat below bottom of head
- Cylinder heads limited to 2 valves per cylinder
- Engine must match brand of tractor
- Intercoolers and /or Aftercoolers not allowed on Diesel and Alcohol but are allowed on Gas.
- Rear of engine must be in stock location for make and model of rear end and transmission housing, with a maximum tolerance of 1-inch adapter plate
- No super chargers allowed
- Turbo Chargers WHEEL—? —-HOUSING
- Single turbo charger of a size not to exceed a 3-inch diameter measured at the front face of the wheel with one single air inlet with no additional openings in compressor housing outside of the 3 inch inlet.
- Compressor wheel must enter into the compressor housing.
- No MAF enhancement will be allowed on alcohol engines larger than 310, all plugs will be welded.
- Diesel 470 cubic inch single charger and 310 cubic inch alcohol can run MAF enhancement.
- Allow diesel engines 360 cubic inch and under 2 (3” intake) chargers – No intercoolers or after coolers – No MAF enhancement.
- No fuel injection pump larger than a 6- cylinder P series pump will be accepted.
- Cubic inch
- OEM tractor rear end and transmission housings only will be accepted, no component tractors allowed.
- Acceptable fuels are diesel fuel, alcohol, and gasoline.
- No oxygen carriers or combustion accelerators will be permitted.
- Weight for the class is 6000 pounds.
- All tractors must carry at least 200 pounds of moveable weight.