Well if you do the calculations it's not that balsy. 6250rpm, with the motor's specs, and that compressor wheel at 18psi. It puts it right around 353whp, So I guess you can take away 20whp for being a small exhaust housing, putting us around 333whp +/- 5%

I measured at 7Krpm before, but that's pushing it a bit me thinks.

Im don't think you're being an ass. I know the calculations, they're usually pretty on. My Civic, Chris's, The Z. almost always spot on. Maybe it's just lucky guesses? but even if Im off, 3/4 isn't bad.