Wow Prater... from reading your next thread about methanol questions, and revealing you are running dirt modified circle track, I have to strongly agree with garyc about "hope and pray" on this 60 over engine, especialy because you cannot block fill a circle track engine and keep it cool. 400s are already notorious for overheating and cracking, even on methanol. I have built and raced many circle track engines, including 400 blocks, but 30 over is about max for a GM 400 block. You probably want to start thinking about a backup engine to have ready...