but look at the cam first.

i agree it is a long shot but worth checking.

pulling the head is a lot of work. i wouldnt want to be around if you did that and the machinist informed you the problem was just a couple of worn lobes on the cam!

in a turbo engine the intake pressure would also mask this, i think.
but it would show up on a compression test at 3.5 rpm.

tom w

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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.