For those who believe that there's never enough, the 168HP Polaris ProStar® Turbo H.O. engine takes extreme performance to a entirely new level. The ProStar® Turbo H.O. is the most powerful RZR® engine available from the factory for unequaled power, torque, durability and off-road excitement. The new engine is built for performance and durability with forged pistons, a 270 degree firing order crankshaft, high strength connecting rods, closed deck cylinder and sodium filled exhaust valves. To control the massive power delivered by the ProStar® Turbo H.O., the engine management system has also been updated with improved knock detection and boost control as well as high flow fuel injectors and new cam shafts. All of these systems allow the engine to deliver maximum power under all conditions.