Dyno'd the Magnum.

Stock magnum pistons are hypereutectics. They are much tougher than old school cast pistons. Detonation with boost or nitrous will kill them pretty fast, but I've never heard of anyone breaking one N/A.

I ran 40* on mine for a little while last summer, but again, mine made best power at 38*

Yeah, that knockoff intake has some issues. Port alignment on mine was just terrible, and the runners are smaller than a real Air Gap. Also the runner shape is just "however they felt like doing it" without regard for the fact that it actually matters for horsepower.

What RPM was your HP peak?