225 pro max fuel pressure?

[kjdoo4]

I have a fresh rebuilt pro max that I did a vst delete to. I'm putting the adjustable regulator on it and want to double check what people are setting the fuel pressure to. Book says anywhere from 36-39 is ok. should that be engine running or key on engine off pressure? The reason I want to double check is because of the swing the regulator makes with vacuum applied to it. Thanks, Kevin

[nitro_rat]

Key on engine off it should be 39. At idle vacuum will pull it down to 35-36. At low vacuum like WOT it should be back to 39.

[kjdoo4]

Thank you for the info