waste-gate actuator

[McGivern]

I have a wasted-gated housing that I plan to install on my truck. The actuator diaphram on this unit is bad and must be replaced. I'd like to have the waste gate activate somewhere between 20 and 25 psi (closer to 20). I think the actuaote on the housing was for around 15 psi. Can anyone help me with part numbers/ sources here?



Thanks , Mark