I found a very cool Kart track where they have not only race chassis classes but 2 separate classes for yard kart frames. The idea is that you take a random kart frame, strip it and rebuild with race components. One class is 6.5 HP and the other is completely open. Tech is simple, kill switch and brakes. Everything else goes. Most are running old Manco Dingo frames. My question is, where is the tipping point between usable power and just blown motors? I run the 6.5 class with either predator or clone engines and I build them up a little more all the time. Cam, springs, flywheel.... still gravity feeding a stock but re-jetted carb. Just looking for a little direction. I blew one up last month and will probably blow one this month (old block). But as I restock with predator motors I’d like to get a full season out of the next couple....