318 Are my pistons too deep in the hole...............

[bandit67]

Hi Guys, trying get my numbers matchin 318 back together.  Had the block punched 30 over and bought new cast pistons.  Stock rods were full floating and are in great shape. Placed old stock flat top piston and new replacement on same piston pin and both seemed to be at same height. Had crank turned, and installed rod assembly with new bearings.  Pistons  now measure around  .075 down below deck.  This seems way to low. Checked with my books and can not find any numbers  in reference to what is expected.  The motor is 1972.  The replacement pistons  also have four valve notches  as compared to the original flat tops. I wish to get compression up to 10. 1 if possible. I have the thinnest head gaskets Mopars makes. I had ask for heads to shaved as much as possible , but on pick up was told they just surfaced ground them.  Should I get the blocked decked  or find new pistons.........any opinions...........John

[Chryco Psycho]

I would rather use a taller piston than try to deck the block that far down

[bandit67]

Thanks Chryco, any idea how far down below deck is normal?  Any idea on where to find a taller piston.  Would a stock 67 318 piston be taller........was thinking maybe I just ordered the wrong stuff.........John

[Chryco Psycho]

http://www.csgnetwork.com/compcalc.html

this may help
I do not have any catalogs handy to look for piston options , Posssibly Diamond may have some options