Stock Altered


· Weight Class: 1050 lbs.

· Age limit on class participation: 9 years old and/or physically capable of being in full control of their tractor at all times unassisted.

· Stock Frame (OEM Frame). Rear axle must remain in the stock position. Wheelbase 52” maximum.

· All stock altered tractors must be built to NQS Stock Altered Rules as follows:

· Single cylinder four cycle flathead engines only.

· Engines must be Kohler, Wisconsin, Tecumseh or Briggs.

· Engine blocks must have an OEM stock appearance.

· Engines must be factory productions or their OEM replacement with factory deck height.

· Stock head bolt pattern. Stock head gasket must fit over studs or bolts.

· Stock head bolt location and head bolt size.

· Maximum crankshaft stroke 3.25”

· Maximum engine bore 3.780”

· 36.5000 cubic inches’ limit

· Maximum engine valve size 1.380”

· Maximum engine valve lift .330”

· Maximum carburetor venturi size 1.00”, no air entering after 1.00” restriction, venturi must be round in shape.

· Carburetor must be mounted to the engine with no more than a 1” spacer.

· No reverse port engines allowed, carburetor must go to the original intake port.

· Carburetor must be a stock appearing Kohler­type.

· Billet heads permitted.

· Porting and polishing allowed.

· No external welding or external modifications allowed.

· All thread through finned area is acceptable.

· Welding permitted in crankcase area of the block for repair.

· Must run a factory appearing hood and grill.

· Tractors must have a garden tractor rear­ends.

· Tractors must use stock garden tractor frames.

· Frames must maintain factory length.

· Wheelbase: 52” maximum

· All 30 cubic inch tractors will be allowed to run in this class. If there are more than 3 they will have their own class. 30 cubic inch tractors will follow NQS 30 cubic inch rules. Fuel: Alcohol or gasoline allowed. No Nitrated or Oxidized fuels allowed.