I'll change the bet to 1 hour at full RPMs (is that a fairer bet)?
It would be a fantasy bet (funny money) and parimutuel in the fantasy payout.
One of our members is working on a "blown/supercharged" GMC 302 (I think that is what people might call it in the Hi-Po Shop?). He and his buddies will correctly (and, safely) measure HP. Maybe he will report back here?