318 with 360 crank-another peeing contest

dartjack said

The stroke difference is .270 but the piston only comes up half of that. The other half is on the bottom of the travel. Figuring that most teens have a
-.060 below deck piston or so then the piston will come out of the hole about .070 or less. The first 340's came out .010 if I remember correctly and had a 10.5 CR. The more input on this post the better.

Thanks

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Oh yeah, I forgot to cut the difference in half. But still, that's .135 out of the hole, minus .060 that they are usually in the hole...comes out to .075 out of the hole. That's a lot. You could probably knock a little off the top of the piston, but I wouldn't think you could take more than .030-.040 off, which still leaves it .035-.045 out of the hole, which is still a lot. You'd need to run a thick head gasket and not go too high on the cam lift. Most builders keep it zero to maybe .020 above deck