how much horsepower?

I have a little high boost experience with GM stovebolts... Ring seal is a big issue on it because the bores move all over... As you can't get a better block (meaning thicker walls) it was sleeved, the deck completely modified, and the block filled (runs on mechanically injected methanol). Oil coming out everywhere is a sure sign of pressure leaking by the rings and the block "moving around" under the load. Turbos won't kill the mains although I'd assume he did something down there.