Not all gears are created equal. According to GearFx's general manager Jeff "Fuzzy" Horton , they've tested a lot of gears and the most consistent and true gears they've found are the Stealth Series ring and pinion parts from US Gear. US Gear uses a new gear cutting tech on these called face hobbing, which creates a continuous and more consistent cut on all teeth of the ring and pinion at the same time. We did the math and decided that 3.70 gears would be our best bet for staying in our engine's power band, so that was the gears we picked up through Summit Racing (PN 07-890370SS). Here you can see a factory finished Stea l th ring gear on the right and one on the left that has gone through GearFx's REM ISF (Isotropic Superfinish) process. In fancy speak , the process produces a nonlinear, low Ra, finish that improves wear and reduces friction. To us laymen the gears are surface polished, but it's way more involved than that.