Billet head kit with +1mm stroker crank for the Go-Ped GP460 and CY46 engine. Increase engine size to 47.1cc. Includes billet head shell, machined cylinder, stroker crankshaft, special stroker dome, piston, piston ring, circlips, copper head gasket, base gasket, bolts, and spark plug. This kit will increase power throughout and it is the largest displacement kit available for the GP460 engine. Select dome size based on the octane level of fuel you will be using.