how long were you able to run the engine before it overheated? the valves may need seating a bit more.

i'd try to run it a bit more before tearing off the head, to do that you'll need to solve your overheat problem.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.