5900 Pro-Field Tractor Rules

  1. 5900 lb. turbo and 5900 lb. naturally aspirated tractors will pull in the same class.
  2. Sheet metal needs to be in the family of the tractor. Any ag motor with like brand ag rear end.
  3. Industrial tractor type engines only, no automotive type engines.
  4. Primary fuel shall be diesel or pump gas, no alcohol. No electronic controlled fuel injection allowed on gasoline or diesel engine.  No throttle base injection systems.
  5. No nitrous oxide or propane injection system allowed.
  6. Diesel tractors are allowed to run a P pump and gasoline tractors are allowed one 4 barrel carburetor.
  7. Diesel tractors may be converted to gasoline fuel system.
  8. Tractors can pull in higher weight classes, but must comply with all safety rules for that class.
  9. Maximum tire size 18.4x38
  10. Naturally aspirated, maximum of 650 cubic inch Turbo tractors shall have a 360 cubic inch limit.
  11. Tractors equipped with turbo or supercharger shall comply with the following additional rules:
    1. 3000 RPM limit. Tractors shall have operative, factory-equipped governors which will be checked by: visual retarding movement of the throttle linkage from governor case to carburetor; and audible acceleration when clutch is engaged while holding brakes on with tractor in high gear. Tractor shall be equipped with tack cable with one magnet (female connection from tractor) to hook to sled. Verification and consequences, for excessive RPM, shall be the same as Hot Stock classes.
    2. Water & alcohol mix injection into intake allowed.

5900 Classic Modified Tractor Class

  1. All tractors must be neatly painted. Tractors are intended to look like a stock farm tractor that has an automotive V-8 neatly installed.
  2. No extended or widened hoods.
  3. Raised carburetor enclosures are allowed.
  4. A maximum of 410 cubic inch (big block allowed) displacement with a 1% tolerance.
  5. Tractors may run one (1) cast iron automotive block and OEM and cast iron heads.
  6. No overhead cams.
  7. Enhanced electrical systems are allowed.
  8. No magnetos.
  9. Electric water pumps, electric fans, and electric fuel pumps are allowed.
  10. No tunnel ram or sheet metal intakes.
  11. No flap or rain cap type covers on exhaust.
  12. Tractors are to be naturally aspirated with a single gasoline carburetor.
  13. No nitrous oxide, water, or alcohol injection.
  14. No nitro methane or methane fuel additives allowed.
  15. 18.4x38 tire size maximum. Any cut and any rim width.
  16. Stock frames or like replacements are allowed. Example: tractors with cast iron tub chassis my convert to side rail frames.
  17. Transmission, rear end and axle housings must match factory sheet metal, dash, and hood.
  18. No lengthened or widened hoods.
  19. All tractors must have a wide front.
  20. Centerline of front axle may be no more than 12 inches in front of OEM axle location.
  21. Batteries and fuel tanks may be remote located in front of grille.
  22. No part of tractor including front weights may extend more than 11 feet in front of the centerline of the rear axle.
  23. Weights may not extend beyond the rearmost point of the rear tires.
  24. Adjustable draw bars must be stationary in all directions.