hello im playing around with boost control and run in to a problem it hits peak boost around 3600 rpm and about 12 psi then by around 6500 rpm its at 7.5 psi the fall off is linear.
the more duty you give the boost solenoid the bigger the problem for instance if i up the duty and hit 23 psi it will peak just under 4000 rpm but again by 6500 rpm it will have dropped to around 14 psi i've leak tested the boost system but doesn't seem to be any leaks its a 4x4 t3 turbo on a zetec engine.