The XE230/236 is a N/A grind because of the tight duration and a 112LSA (.544/.556" w/1.6RR's). I had mine custom ground on a 114LSA incase I wanted to add a little boost or a little juice. My compression is still around stock, but lots of LT1's run 6psi. I will probably only be making 5psi or so from the bleedoff from the cam.

I have the MSD timing retard with the kit (adjustable from 1-3 degrees per # boost). Is that also the ignition box, so I only needa coil?

 

Lots of LT1s run 6# on stock compression, but that cam you have is gonna act like a blower cam and increase your cylinder pressure. Yeah, a tight LSA will allow your expensive boost to blow out the exhaust, but it will also keep your stock internals from going "kaboom." I'm afraid my knowlege in the area is far from complete, but I know it works about like that. I just wouldn't pully up if I were you.

 

I think you mean decrease it compared to say a stock cam because pressure is bled off.