1.   Stock engines (block, stroke, heads, valve covers, intake manifold, carburetor). No dome pistons allowed. Engine size must not exceed 39 cubic inches (allows for .030" overbore) for ohv motors or 48 cubic inches (allows for .020 overbore) for flatheads. Interchanging parts between different brand motors WILL NOT BE ALLOWED.

2.   Stock downdraft carburetor may have adjustable needle added. No other alterations allowed. OEM accelerator pump carburetor is allowed. No other types of carburetors allowed. Maximum one (1) carb with (1) venturi allowed. No turbos or pressurized intakes.

3.   No two-barrel manifolds and no aftermarket manifolds allowed. Cutting or welding on manifold is not allowed. Vertical intake carb adapter is allowed.

4.   No reverse port engines allowed. Manifolds and carburetor must go to the original stock ports.

5.   Stock heads may be reworked, but recast or aftermarket heads are not allowed. Porting and polishing allowed. OEM closed chamber heads are allowed. No external welding or other external modifications allowed. Must use stock intake and exhaust bolt pattern and location.

6.   Engines must use stock lift cams, stock length valves, and stock rocker arms. Pushrod guide plates allowed on OHV twins. Aftermarket lifters are allowed but must be flat tappet, no roller lifters.

7.   Engine must have been available in a lawn or garden tractor from an oem manufacturer not to exceed any other rules such as horsepower, cubic inch, cylinders, or class size rules, etc., and must be oem stock production garden tractor engine. Aftermarket blocks are not allowed. It is up to the tractor owner to provide documentation to prove eligibility, such as oem tractor manufacturer, tractor model, and engine specs such as cylinders, cubic inch, and horsepower rating.

8.   No rpm limit but steel flywheels are REQUIRED.

9.   Engines must run gasoline, E10, E85 only; service station pumped gasoline, no additives. Racing gas is allowed.

10.   Straight pipes and chrome air cleaners allowed.

11.   Must run a factory appearing hood and grill, use garden tractor rear-ends and stock garden tractor frames that are factory length with a maximum wheelbase length of 52 inches.

12.   May strengthen drive train to prevent breakage. (Reared, driveshaft, clutch, etc.) Altering gear ratios is allowed.

13.   Bar tires are allowed; but no v-cut pulling tires allowed. Tires must be ag type bars. No double cutting of tires, no adding bars, but can single cut the bars in any fashion. No cut turf tires allowed.

14.   Rear tire size: 26 x 12 x 12 maximum.

15.   Aluminum wheels are allowed.

16.   Clutch covers and flywheel shields are required. Minimum thickness 1/8 inch steel or 3/16 inch aluminum.

17.   Driveshafts must have a support bearing in the center or driveshaft loop.

18.   Engine must shielded by 1/8 inch steel or 3/16 inch aluminum on external side of cylinder extending from head gasket to frame. Shield must be attached to frame at the bottom and to flywheel shield at the top to make rigid.

19.   Engines must have a hold down restraint installed to prevent the cylinder and head from separating from the block.

20.   Bumper bars are required. These are a vertical bar at least 6" long mounted on rear most part of wheelie bars. Vertical bumper bar must be even with or behind back face of wheelie wheel or skid.

21.   Tractors must have WORKING kill switch fastened to the rear of the tractor in such a way that it does NOT interfere with weights or sled hitching device. The connector must be fitted with a ring with a minimum of 1.5" inside diameter.

22.   A minimum 1 1/2 pound dry chemical working fire extinguisher or equivalent. A gauge on the fire extinguisher is required or an inspection and recharge tag not more than two years old. They can either be dry chemical or CO/2-type extinguishers.

23.   Tractors must have deadman throttle with return springs on the pedal and the carburetor.

24.   Drivers must wear helmets that meet minimum Snell 95 requirements. No football, baseball or toy helmets.

25.   Drivers must wear long pants and boots. No sandals or open toes.