Performance drop off

[zx_volcane]

If that's a stock engine, I doubt it'll last too long running that kind of boost.

surely boost doesn't mean a thing unless you put in the fuel to burn it - adding a few 10s of psi down the inlet isn't going to increase peak cylinder pressures significantly over what they are already, ie stupidly high.

iirc this has been running on a 9mm

sure, chuck in a 11mm and get too happy with the static advance and you're pushing your luck