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MLC - Mid Life Crisis
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My buddy has an early model Nova and found a short block 396 for it. He is looking to put on the 781 heads. Since he lives out in BFE, he sent me a picture of the block and the pistons. He says they are pretty flat. However, the look to be somewhat domed to me. Maybe it is just my eyes. Can anyone tell what kind of pistons these are. He is looking for a pump gas bbc.

3ne3kf3o55V05Q65U0b4p8eb2f20023a61c22.jpg
 

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I would agree with wizbang as long as the short block used it's orig closed chamber heads of around 107 cc chamber bathtub shape that matches the piston you see in the pic.
the 781 head is something close to 118 cc and will drop the comp a full point so 9.25 give or take a little on head gsk thickness and piston to deck,but that will get you close.
Good luck with your build.
 

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MLC - Mid Life Crisis
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Discussion Starter #4
Thanks guys, I will let him know. Personally, I told him a tall deck should be in order but it is a "budget" build.
 

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1/4" dome 291 casting..109cc i think....11.0:1 on a 427
When i got it was [email protected]*....running 50% av gas....haven't had much time to mess with due to a fram mal***ction but it seemed happy with 50/50 89-91 octane and 34*....so i guess that is pump gas-able...that was with a 'about .040 head gasket....going steel shim this time
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My buddy has an early model Nova and found a short block 396 for it. He is looking to put on the 781 heads. Since he lives out in BFE, he sent me a picture of the block and the pistons. He says they are pretty flat. However, the look to be somewhat domed to me. Maybe it is just my eyes. Can anyone tell what kind of pistons these are. He is looking for a pump gas bbc.

View attachment 114791

You should confirm the bore size, the 396 had a bore of 4.096 and the 427 had a bore of 4.250
 
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