The Traxxas TRX Pro.15 race engine with short IPS shaft and Pull Start offers you a new level of nitro performance. This exciting engine will satisfy the demanding drivers, who believe you can never have too much horsepower. It fits in the same space and uses the same engine mounts as a .12, but the the TRX Pro.15 has a 20% larger displacement than a .12 engine. It includes high-tech features such as a grooved oil-ring piston for long life, a trick machined aluminum cooling head, ball bearings, finned aluminum backplate, and a channeled-beam connecting rod which improves oil flow. The carburetor is all new, with a larger 6mm intake and reuseable low-restriction foam air cleaners. Double O-ring seals on both the high and low-speed needles eliminate power-robbing air leaks. The TRX Pro.15 is an incredibly rugged and long-lasting powerhouse, with its strict quality control, ABC (aluminum, brass, chrome) construction, and the toughest recoil pull starter available.