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ironridge
06-06-2009, 14:11
Question here. I have been looking around for a spec on stock piston protrusion above/below the deck and can't seem to find anything concrete. Anybody have one or ever measured a stock engine.:confused:

Thanks in advance

john8662
06-07-2009, 00:14
The ideal protrusion is .006" or a little less .004" - .007" for a STD compression engine.

ironridge
06-07-2009, 12:19
Thanks, mine go from 0-6k. So I guess thats in line.

john8662
06-07-2009, 18:44
Your variance is likely due to the rod length too, if you've had the rods reman'ed the centering up of the pin bushings during bore/hone is essential, and hard to do by most shops, they're usually just close.

Where you'll see this variance, is here.

I'd prefer during assembly that they be within .002" of each other. It'll work though as you're in no danger of piston to valve interference, that is if we're talking zero deck to .006". Six Thousandths of an inch.

J