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Discussion Starter #1
On a stock 91 302, should the piston be even with the block deck when at TDC or slightly in the hole. If it should be in the hole, by how much?

Thanks
 

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Stock quench should be about .040 and figuring that head gaskets are about .038 compressed, the piston should be about .002 below the deck. Somebody correct me if I am wrong...
 

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I would look for a deck height from .010" in the hole to .000" deck height. The key is that they are all the same, not one end of the block .015" and the other end .005". Most steel rod cars can run a .000" deck height without any problems. An aluminum rod motor should be .050" in the block....

The same goes for combustion chamber size. You want them as equal as possible.
 

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It is common for stock motors to have the piston down in the bore at tdc. Sort of a production tolerance thing as zero deck or a slight positive deck is much better for quench and flame travel. However, achieving zero deck in high volume, low priced profit-margin focused mass production environments isn't happening.
 
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