i was wondering what sort of power a 96 wrx gearbox can handle.mine has noisy bearings in first gear.my power about 350 bhp and about 320lbs.

 

It is the torque that does it, and i think you are right at the 'weak' point.
Time for a 'gearbox re-think'

fit a V6 or later box/diff or a rebuilt 5 speed or the 6speeder option =
£800 £2800 £2000

Join the club. I'm in the same boat (Sti v3 @ 340 lbft)
Graham