I wouldn't guess. Do a wide open throttle run and pull a plug shortly after. Adjust up or down according to the color of the plug. That's how I do it. For your mods you will be in the area of 36-41psi.
k...now that his got answered and i dont want to start my own thread on it. how bout me?? mods in sig. i usually have it at about 41ish but was thinkin it might be high cause it smells like too much gas but the plugs are pretty white.
I originally typed that Vibrant; then I edited it before posting, because I got mixed results when I double checked my sources. Thanks for the correction.