Originally Posted by dyezak

I used to rebuild these trannys, usually popping out of gear is a bent shift fork, the gears aren't engaging properly, and when power is applied they seperate and you pop out of gear. You don't have to bend a shift fork much for this to happen, .05" is enough. Usually a bent shift fork is caused by people getting lockout issues from a heavy clutch disk (stock type full face disk). The person gets lockout, tries to force it in gear, bends the fork. Problem is when you put full power on a partially engaged gear you are reducing your contact surface and have the possibility of stripping gears. One of my good friends did this with about 350whp, so it's not big HP cars that have to worry, it's all cars.

Shift forks are cheap (roughly $100-125 new). Buy a new 3/4 shift fork and drop it in, along with either adjusting your current clutch to get rid of lockout, or a lighter clutch disk. Shift forks, clutch and Redline (heavy) shockproof will have you fixed up. Since you already dissasembled your tranny I assume this will be no problem for you.

Oh, and if you have the cash, get a twin disk to eliminate your lockout.