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Discussion Starter #1
How much overbore can a cleveland take before it gets to much? It looks like I'll be going 30 over. I know the walls are thinner than normal on the cleveland, but I don't know what a reasonable overbore would be.
 

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My best advice is to have the block sonic tested for cylinder thickness and core shift before you spend the money to have it bored! No sense spending the money and have a nice .030 overbore if the cylinder walls are getting porous! Clevelands get iffy at .030 overbore. I'd go .020 first if I could find the pistons...

That said, AlphaCat's original 4-bolt main Cleveland is .030 with forged Boss 351-style domed pistons. Ha! Just try finding those around these days! LOL!

BetaCat is still a stock bore 4-bolt main Cleveland with its original cast pistons.
 

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Discussion Starter #3
When I picked my motor up from the machine shop they had it bored out 30 over and the shortblock assembled, all without asking me anything. They didn't sonic test or anything. They claim there were small imperfections in one cylinder wall that it needed to go 30 out to remove them. I saw the groves and they were 10 maybe 20 out, but no way 30. Anyway, the damage is done. Can a sonic test be done with the crank and pistons in the short block. If it can maybe i'll take it somewhere else.
 
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