im gonna add to this qtiger. if you have worn synchros, you can bronze face the teeth and that will cure that problem. if you want to pick up 5% hp you should rebuild the tranny with straight face gears. granted this isnt a normal daily driver fix, but it does pick up hp, thusly speed. but be warned, if you hate the noise reverse makes, dont think straight face. the faster you wind a straight face gear, the higher pitch the whine becomes.

quaiffe makes the best lsd on the market as far as im concerned. it is a Torsen type II lsd, meaning it has no clutch packs or anything else to prematurely wear. it is strictly gears that drives/handles almost identical to an open diff. if your familiar with subaru's you should be aware they use viscous type lsd's which have clutch packs in them. and if you do know subaru's you might have heard people talk about how it "skips" thru turns. this occurs because viscous lsd's lock up from heat, and when taking high speed turns, some wheels dont want to rotate, in turn causing the clutch packs in the lsd to slip, causing friction which in turn heats them up. quaiffe/torsen type lsd's do not suffer from this because it is a complete gear setup so you wont suffer from torque input steering. it rolls right thru the powerband with no problem, keeping power almost equally distributed to both drive wheels.