What do you guy reckon is a safe boost limit on my car.

Sierra 2.0 DOHC 8V Turbo Technics
Running 10.5:1 Compression
Lightened bottom end and 285 cams
Cast Pistons
Rebuilt less than 8000 miles ago by Ratty of the boards and he replaced everything with vey big reciepts

Turbo technics say a very reserve 6psi
However iv ran 9psi in the past on a boggo engine.(which went bang at 160,000

Its running 8 at the mo so would you leave at 8-9psi which will give about 200 bhp or can we risk it.

Could it be increased with a bigger intercooler or water injection e.t.c

Your thoughts please