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Super Modified 4wd Trucks

Super Modified 4WD

1.       Maximum engine size of 500 cubic inch for supercharged or turbocharged engines with a maximum wheelbase of 170 inches. There will be a 1% tolerance on all engine measurements.

2.       Weight of the vehicle and driver before, during, and after pull shall be as follows:

a.       170 inch wheelbase – 6600 lbs.

b.      133 inch wheelbase – 6300 lbs.

3.       Hitch point for the 170 inch wheelbase trucks can be no less than 18 inches and no more than 20 inches from center of rear axle with a maximum height of 26 inches before, during, and after pulling. Hitch point for the 133 inch wheelbase trucks shall be 48 inches from the center of the rear axle. The hitch height for this class will be 26 inches.

4.       Trucks may only run an 871 conventional supercharger with a 60 degree or less rotor angle at a maximum of 53% overdrive. No high Helix or Retrofit superchargers allowed.

5.       Trucks with a wheelbase of 133 inches may run as Modified or Super Modified by Ken-Ten or NTPA rules with a conventional 871 supercharger or less at a maximum of 53.8% overdrive.

6.       Rear Tires must track front tires at least 50%.

7.       On 170 inch wheelbase trucks, engine blocks must be OEM style and be cast iron/steel.

8.       Pro-stock trucks may run in class by KTPA, NTPA, BOB or Ken-Ten rules.

9.       Fuel must be either alcohol or TNT spec fuel.

10.   Some type of bed must be used, either original or flat, and must have side rails.

11.   Any type of body may be used, metal or fiberglass.

12.   Must have front fenders, windshield and on-board fire extinguisher.

13.   Blower drives must be shielded and blower restraints must be used.

14.   Exposed turbochargers must be shielded 360 degrees with 0.060 inch metal.

15.   Rear of the engine block shall be located no more forward than center of front axle. Trucks shall be single engine only.

16.   Trucks may run 18.4 x 16.1 farm implement tires that have a maximum of 18 inch tread and 40 inch diameter. Tires must have brand name and size on them. 

 For a printable version of these rules, click the link below.

Melanie Wiley,
Aug 25, 2018, 1:38 PM