Dose anybody know where i can get a uprated alternator for a 95 impreza from standard is about 75A i think i need around 150A ?????

 

Demon Tweeks do them but they are ££££'s IIRC 150A is one hella size of an alt. Might be worth phoning round some of the bigger car audio installers, Prestige etc, they'll be able to advise on your requirements.
Also remeber that you'll need to upgrade some of the wiring to handle the current.

John.