Ive been running 12 psi through a 20,000 km old standard a12 (standard head gasket) for nearly 2 years it puts out 106hp I've had no troubles with it the motor just changed out first broken diff this week. its probably done 6-7000kms with turbo on it now. I had it at the drags about a year ago with a 3.7 diff in it it only got 15.6 sec 134 kph in 3rd gear @6800 revs I couldn't get it off the line quick because the clutch would slip or wheel spin
You should keep it and spend some money on a tune I got mine done at Ova boost in Malaga

Cheers Brad