Can anyone tell me what boost preasure my STI4 type R should be running at?
At the moment my apexi boost gauge reads 1.6bar at full boost, is this correct?

If your car is standard, that's far too high. Is that "peak" boost, or boost "held".

The cars are prone to overboost, but unless the car has been played with, or a hose is leaking/loose, 1.6bar is much higher than one would expect.

Check all the hoses to, and from the turbo, and solenoid are secure, and particuarly the actuator. Also try another gauge to confirm yours is reading correctly.

Mark.

What is the difference between Peak boost and boost held?

"peak" boost is a spike, or overboost, just held for a very short time. "Held" boost, is the level of boost maintained.

Mark.

Good grief.....1.6bar.

I've heard of some quite heavily modified stuff running that much ~ but as standard it sounds high.

I'd be wary of piston damage on that much boost unless its been modified to take it.

I've heard of pistons being holed (or worse) on sustained high boost.

don't mean to sound all doom and gloom, but I've been there and bought the T-shirt...and the pistons !!! http://bbs.scoobynet.co.uk/frown.gif

Mark