from your description it sounds like a valve issue. but as noted it also could have broken a ring (unlikely), eaten a hole in a piston, unlikely, or blown a head gasket, more likely. i dont think i have ever heard of a sudden loss of compression except as a valve loss. but the hole in the piston seems possible too. if it were a hole in the piston when the car is running there would be a whole lot of violent blow by coming out the oil filler cap. it might even blow out the dipstick. a holed valve would make a lot of noise in the intake if an intake valve and in the exhaust if an ex valve.

in any case probably not an easy fix.

the only fix possible that wouldnt be too bad is if it were a stuck valve or a broken valve spring.

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.