Skip to content

Section 27 - LIMITED PRO STOCK TRACTORS (LPS)

Unless specifically outlined below in the class specific rules, the Tractor General Rules and the overall General rules outlined above will apply.

27.1 - General Rules

  1. No component chassis.

  2. Limited Pro Stock Tractors will compete at a maximum weight of 9,500 lbs.

  3. All OEM chassis Super Farm rules, including shielding, safety apply to this class.

27.2 - Tires

  1. Tire size allowed is 24.5 X 32 maximum. See General Tractor Rules for dimension. HP pullers tires allowed. Pro Puller Tires are allowed. See general rules for specific information.

27.3 - Engine

  1. No engine larger than 640 cubic inches (+1 percent)

  2. Recast blocks allowed but must be OEM size and spec

  3. No billet blocks allowed.

  4. Big blocks are allowed.

  5. Deck plate allowed up to 1 inch thick.

  6. Engine block must be OEM size and spec agricultural type for that brand of engine.

  7. Recast or billet heads allowed but port location must be same as stock with manifolds and can be no more than 1 inch taller than stock height and must be stock width and length. All ports must be in stock location and the valves have to come in at the stock angle. The stock angle is 90 degrees.

  8. Aftermarket manifolds are allowed and must bolt in original port bolt locations.

  9. No overhead cams.

  10. Maximum 2 valves per cylinder.

  11. No intercoolers or aftercoolers are allowed.

  12. The maximum size injection pump is a 7100 P - pump with maximum size plungers of 16 mm. No 8600 P-pumps. May run 15 ml cast iron housing Sigma’s “MUST BE SENT TO DIESEL PERFORMANCE ENGINE (DPE) FOR INSPECTION AND SEALED”.

  13. Maximum ½-inch spacer allowed between engine block and transmission. (Exempt LSS(AG) Class)

27.4 - Turbocharger

  1. Must use Harts Diesel 4.1 box turbocharger with no alterations allowed.

  2. If turbocharger has been found to have been tampered with, the competitor will receive a 5-year suspension from being able to compete at an OTTPA event. Competitors will have an opportunity to appeal a suspension to the OTTPA Executive Board.

  3. A turbocharger pressure pipe blanket is required

    1. Turbo outlet pressure pipe between the turbocharger and the intake manifold must be wrapped 360 degrees with an OTTPA accepted blanket.

    2. Blanket must be placed as close to compressor housing outlet neck as possible and extend at least 6 (six) inches beyond the first bend in pipe or a minimum blanket length of 18 inches, whichever is longest.

    3. Any pressure pipe shorter than 18-inches must have blanket covering the entire length of pipe.

    4. Blanket must be purchased from an OTTPA approved manufacturer containing a minimum of 5 (five) layers of Kevlar. A blanket displaying a SFI 4.1 certification is accepted but not required.

27.5 - Fuel & Water

  1. VP Racing Fuel is the only fuel that is allowed for use in all pulling vehicles. VP TORQ DX fuel is allowed.

  2. VGM water is the only water injected water that is allowed.

  3. A \$50 fine will be assessed for lack of fuel and water test ports for all classes.

  4. A \$50 fine will be assessed for any minor infractions of fuel or water quality.