Can I bore out my 402 to 4.250 or even .030 over that to a 4.280 bore and make it a 427? The block is a 3969854 casting.
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Can I bore out my 402 to 4.250 or even .030 over that to a 4.280 bore and make it a 427? The block is a 3969854 casting.
SOME, 396-402 blocks will bore to 4.250. I have seen a couple that went .030" over that. It would be wise to have the cylinder walls sonic checked. The vast majority of two bolts get thin spots at .090" over stock bore
Some websites that I have visited say that the 3969854 block was used for a 72 454. Given that information I would think that I could bore it to 4.250 and install 427 pistons. Have you guys got any more information?