Naturally Aspirated Tractor Rules


  1. Drawbars shall meet the following: drawbar to be a minimum of 2 square inches total steel material at any point. This includes the area of the pin with the pin removed. The pin will be a minimum of 7/8 inch. Drawbar must be equipped with a steel hitching device not more than 1.5 x 1.5 square, (or 1.5 round), and with an oblong shaped hole 3.75 inches long and 3 inches wide.
  2. No drawbar support tubes attached above the centerline of the rear axle, unless using the stock drawbar support for that make and model. Absolutely no drawbar supports designed to pull only from, or to be attached only to a point above the centerline of the rear axle.
  3. Drawbar maximum height 20”
  4. Drawbar to be no shorter than 18” from center of axel.


  1. Each competing vehicle must have a working RPM pick up on their vehicle. The pick- up must be a molded sealed plug (Ex: extension cord plug) must be able to be seen and not hidden above the drawbar area. The pick- up MUST be in working order during competition. If a competitor’s pick up does not work at an event, a competitor may be hand tached immediately after leaving the track after a competitive pass. A competitor must be tached trackside. If a competing vehicle leaves the track area before being tached, the vehicle will be disqualified.
  2. If a competitor’s pick up does not work at an event, they have until the next event to repair the problem. A competitor will not be eligible to compete 2 event entries in a row with out a working pick up.
  3. Engine must be stock block or factory replacement for that make or model.
  4. Tractors are limited to 700 cubic inches plus 1% for wear.
  5. Maximum RPM allowed while hooked to sled are as follows for each make and model which are known to compete:
    6 Cyclinders 3,000
    V-8- 3250
  6. All tractors are to be naturally aspirated. No turbochargers, superchargers or add on injection.
  7. No air-cooling agents.
  8. P series injection pumps are allowed. P7100 maximum.
  9. No aluminum or aftermarket heads are allowed
  10. Engine must be stock appearing for that make and model of tractor.


  1. Tractors are to be stock appearing.
  2. All housings must be stock appearing for that make and model of tractor.
  3. Must run OEM axles and axle housings for that make and model of tractor. Modifications of stock housings are acceptable for the fabrication of external brakes. Fabrication should be suitable for weight and speed of vehicle being entered in the class.
  4. Fabricated steering axles are acceptable within OEM wheel base limits per make and model of tractor being entered per IPA board and tech committee approval. Fabrication should be suitable for weight and speed of vehicle being entered in the class.
  5. Fenders are required.

Exhaust Systems

  1. Exhaust must exit vertically with no rain caps.

Fuel and Fuel Containers

  1. No nitrous oxide, oxygen or nitro methane.
  2. Tractors must run on diesel.
  3. No water or alcohol injection.

Kill Switches

  1. All diesel competing vehicles must have an air shut-off or fuel shut off in working at order at all times.
  2. On a diesel tractor, the kill cable must activate the air shut-off or fuel shut off required on a diesel engine. A cable may be used for this purpose but must have positive type enclosed cable for the air shut-off. The cap must have a spring loaded closing mechanism. It is recommended that a gasket / seal arrangement be used to more effectively shut off air flow. Door or rain cap air shut offs (no “butterfly” type) will be required on all self ignition engines with a separate control for the driver. Control for driver not to be the same as for the sled. No electrical operated air shut-offs allowed.
  3. Track officials and/or tech inspectors have the option of checking kill switches as they feel is adequate at any event. It is recommended that all kill switches be check on all competing vehicles at every event.
  4. All kill switches must be mounted independent of drawbar and/or wheelie bars / stabilizer bars.
  5. The kill switch must be located in the rear center (maximum of 6 inches off center in any direction), approx four feet above the hook point.
  6. The breakaway kill switches must have attached to them a minimum of a 2-inch diameter ring, with a minimum 1/8 inch cross-sectional thickness. The cable from the sled will be attached to this ring.
  7. Portion of the kill switch and mounting bracket(s) must be able to withstand 32 pounds of pull per switch when pulled independently or collectively.
  8. If vehicle has kill switch or shut-off located in a legal position, and during the pull it is pulled and the nylon strap is broken, and the presiding judge inspects and finds switch capable of operating properly under normal conditions, vehicle will be allowed to re-pull immediately or drop six positions. Decision to drop must be made before vehicle leaves the track. It is the puller’s responsibility to see that the official checks the switch before leaving the track.
  9. Diesel engines must have a fuel shut-off valve control within easy reach of driver (your normal fuel shut-off on diesel pump). All diesel engines must be equipped with an emergency shutdown air shut-off at the air intake, which can be utilized from the tractor seat.

Stabilizer Bars

  1. Stabilizer bars are required. The drawbar assembly will not in any way be attached to the stabilizer bar assembly.
  2. The stabilizer bar must extend a minimum of 32 inches behind a line drawn from the center of the wheel to the ground. Pad must not be more than 10 inches off the ground at 32-inch point and be measured during hitch check before competition. The stabilizer pad must be a minimum of 5 inches square with a minimum of 20 inches allowed from outside of one pad to the other. No crossbars between stabilizer bars allowed behind point of hook.


  1. Any engine driven fan must be shrouded 360 degrees.
  2. If an Illiana Pullers Association track official or tech official feels a vehicle is unsafe, they have the right not to allow vehicle to pull. Track official or tech official has the right to bar a competition vehicle from competing if he or she believes that the vehicle has a potential safety problem.
  3. A scatter blanket is not required but is STRONGLY RECOMMENDED
  4. All pulling vehicles must be equipped with a minimum of 2 lb Halon type of 2½ lb dry- powder type fire extinguisher, full charged with a gauge, in working condition and convenient to the operator


  1. Maximum size is 18.4-38. No duals, chains or four-wheel drives.
  2. Cut tires allowed
  3. Aluminum wheels allowed


  1. Maximum weight for tractor and driver is 12,000 lbs.
  2. Weights must be safely secured and must not extend rearward beyond rear tires. No weight frame may extend more than 24″ beyond the furthest point of the front of the tractor.

All general rules apply where applicable.