Single cylinder OHV engines only. Clone or Predator 212.
Stock engine with a maximum displacement of 212cc.
Stock engine with a minimum combustion chamber of 26cc. To be checked with a CC nut.
Stock cylinder head is required. No porting or polishing of the Intake/Exhaust runners. No visual alterations may be performed in the runners, bowl area, or around the valve guide. All head gaskets are legal.
Stock crankshaft unaltered, 2.165” maximum stroke.
Unaltered SFI-approved flywheel required.
Any length connecting rod is legal. Billet aluminum is legal.
Stock unaltered piston only (2.766” maximum).
Stock camshaft cores only, ez-spin assembly must remain as stock. Max intake lift on cam .225"-min .215" lift taken at push rod. Max intake lift at the valve (.261" for Hemi/ .236" for Wedge Head) taken on the valve spring retainer with zero lash. Max exhaust lift on the cam .232"-min .222" lift taken at pushrod. Max exhaust lift at the valve (.267" for Hemi/ .243" for Wedge Head) taken on the valve spring retainer with zero lash.
Stock rocker arms unaltered (Non-Hemi 1:1 ratio max, Hemi 1:1.1 ratio max).
Stock lifters unaltered.
Any push rods are legal.
Stock valves and valve size for the make/model of the head. Stainless replacements OK but must remain stock size for that head. Reaming Valve guide to accept stainless valves also permitted.
Valve Spring Installed Height Minimum .815 Maximum Spring Tension of 10.8 at a Height of .850 Max Wire Diameter Of .071”.
Any retainers and keepers legal.
Stock valve cover unaltered (You may install fuel pump port).
Stock side cover unaltered. Pulse fitting OK.
Any ignition coil is legal (wire and boot non-tech item).
Exhaust: Any header (Must not extend past the rear bumper).
Stock appearing clone carburetor measuring a maximum .615 at the Venturi and .751” at the exit (Measured with ‘NO-GO’ gauge at the entry of the runner, plus a roundness check of venturi. Venturi must be round. No odd shapes. (i.e. egg or ‘D’ shape). Choke may be removed. Any attempt to draw air past carb will be disqualified.
Pump gas only baseline designated by track.
Any air filter and/or adapter is legal.
Aftermarket carburetor spacers and insulators are illegal.
Electric starter and pull starters are legal.
Removal of governor and/or governor components is legal (Plugging holes legal).
Removal of oil sensor and/or oil sensor components is legal (Plugging holes legal).