Take your Mitsubishi Evolution X GSR to the next level with the Tomioka Racing upgraded final drives. With 4.18 ratio, the TR final drive gear will significantly reduce the RPMs at cruising speed of the Evolution X. TR transmission components are designed to withstand extreme on and off throttle shock loads produced during racing. By cutting to exacting tolerances from SAE8620 alloy and put through heat treatment with our own proprietary process, TR final drives are the benchmark of EVO performance gears.Through the use of state of the art 3D modeling CAD software with finite element analysis, our optimized gear tooth profile helps to increase tooth strength. This ensures reduced friction and minimal parasitic loss. Our gear testing includes extreme use from one of the most well known EVO transmission builders in the industry. This kind of torture is meant to ensure that not only are our gears strong enough to handle the shock loads encountered during race use they are also durable enough to handle the variable loads encountered during day-to-day street driving.