(Yeah, I realize this is not a math forum...lol...differentials...triple nerd score ) Hey everyone, just had a quick question about upgrading the differential on my car. As far as I know, it's still the factory unit, which begs the question of what the final drive ratio is. I've heard talk about different final drive ratios, and wanted to know what is best for my situation. I do a decent amount of highway driving, and the revs get pretty high at speed (around 2500 at 60 mph). Also, does this tie into limited-slip units as well? That'll be a direction in which I want to head, too. Any insights?