[puddy]

Originally Posted by jwasbury

Leakdown test should answer your question definitively.

My 1979 did not smoke on startup or while running, but had 40% leakdown on #6 cylinder. Upon teardown the problem was obvious. #6 piston at some point got excessively hot, and the crown deformed, rings broke and were no longer sealing properly. The car ran great and was the fastest thing I'd ever driven even with the internal issues. The big clue that prompted me to test leakdown was after spending a fair amount of $ on mods, my car would not out pull a relatively less modded car.

Short of the leakdown test, the only symptoms of a problem were: high oil consumption, less than expected performance from modifications, and an exhaust like puffing of smoke from the oil filler (blowby gases from crankcase)

That's very interesting, I wonder if I may have a similar issue? My car has been tracked a lot and has seen excessive heat at some point. Enough to melt the backside of the rear reflector and left turn signal, also dried out the engine rubber to a solid brittle plastic and burned paint off the inside of the body behind the rear bumper near the turbo. I'll be doing a leak down test soon. And will post results.