Powder Freaks 912 bb for the Ski Doo G4 & G5. Kit comes with the following. Cylinders bored and ported, rave valves machined, Powder Freaks Billet Head, pistons, gaskets, wrist pin brgs, thermostat housing and ecu flash. Send in your cylinder and rave valves for machining. Dyno results are from our in house dyno with Jaws ypipe and tuned pipe. This Kit is a pump gas 91 octane kit. Race motors are also available. Call for info