I would say that if it melted from the top down then oil has nothing to do with it. IMO detonation and being way too lean may have caused a melt down. Thanks. We looked at that, but it wasn't lean...normal coloration on last piston, head, valves, plug and nothing changed to exhaust or carb. Wiseco engineer determined it was an oiling problem. We also made sure the lines were clean. I'd like to find a high volume oil pump, but apparently that's only a hotrod car kinda thing to do.