have a 1995 (import) wrx, got stailess exhaust, piper cross industion kit, and a bleed valve. It currently runs 0.8-1bar boost.Goes like stink! What pressure can i go to safely, and do i need a different ECU ( STI) for 1.1 bar?

 

Use a bleed valve very carefully. You say the word 'safely'.. To raise boost safely speak to Scott.T, Jolly Green Monster, ESL, Bob Rawle to name just a few. They'll be able to remap your car. Some options are as little as £200. Personally I went for the ESL chip..

 

Forget changing the ECU to another car, take off the bleed valve, reconnect the boost solenoid and buy a chip from scott.T (polar performance):
PolarPerformance

Will be mapped for 1.1bar and fueling adjusted accordingly. Using a bleed valve without a wideband lamda and some sort of knock detection is likely to end with a blow engine unless you are very conservative with how much you up the boost(and then whats the point as you will not see any gains)

Scott.T's chips have been proven time and time again on many cars which now have over 100k miles on them with no issues, I bought one from ESL who have since stopped making them I believe and its the best £200 I have spent on the car.

If you have a wagon then you will need to let whoever you buy the chip from know as its got a smaller turbo and the maps are not interchangeable.

 

One for sale here

 

Yes, If I were you I'd buy that - its a bargain at £100. Usually sell for £200 ish on ebay or from scott.T