[KingLT1]

A head gasket failure doesn't mean the 1400hp rated engine is at fault. For starters, you were running too hot of a plug imo. A 6510 is a projected tip 7 heat range. At your power level you should have a non-projected tip 8 heat range. At bare minimum a Brisk RR12. With Meth and Ethanol fuels, you won't always get knock when cylinder temp and pressure is getting excessive. You could have also been running too much timing. Hard saying without looking at the plugs after a pull to see where the timing mark is on the strap. Last log I had seen of your old combo, the blower was maxed to make the power you want. Maybe consider putting a 427 in it and run 15-16psi instead of 19-20psi. You can't do at 6000ft what everyone else is doing at sea level. You are dealing with a 20% loss in efficiency due to air density.... everything has to work harder to make power.