quick question
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Intermediate
Joined: Feb 2020
Posts: 40
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quick question
i just bought a used block and i have to get the cylinders bored as there was some rust and light pitting on the sleeves. anyway , the machinst sai they make 3 sizes over stock, 10 over, 20 over and 30 over. im not a mechanic and i dont speak the language so i dont really know for sure what that means. my question is, depending on how much he has to bore, what size piston would i need for each size? thanks in advance.
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Joined: Aug 2018
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From: South Hill Wa
2022 C5 of the Year Finalist - Modified
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Aluminum block?
Factory aluminum blocks don't get bored out per say. They can be oversized a smidge but not much.
If it's iron block that is a whole different ball game.
Of course there are exceptions to all of this depending on how much money you have.
Factory aluminum blocks don't get bored out per say. They can be oversized a smidge but not much.
If it's iron block that is a whole different ball game.
Of course there are exceptions to all of this depending on how much money you have.
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From: Thunder Bay
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To answer your question..
"10 over" means the machinist bores the block/sleeve 0.010" larger than stock. The result is that you have to buy "10 over" pistons and rings to match.
If it was my block, I'd pick the smallest overbore that's required. Leaves some room for next time and the larger the overbore....results in thinner sleeves which isn't great for durability or heat changes.
"10 over" means the machinist bores the block/sleeve 0.010" larger than stock. The result is that you have to buy "10 over" pistons and rings to match.
If it was my block, I'd pick the smallest overbore that's required. Leaves some room for next time and the larger the overbore....results in thinner sleeves which isn't great for durability or heat changes.
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To answer your question..
"10 over" means the machinist bores the block/sleeve 0.010" larger than stock. The result is that you have to buy "10 over" pistons and rings to match.
If it was my block, I'd pick the smallest overbore that's required. Leaves some room for next time and the larger the overbore....results in thinner sleeves which isn't great for durability or heat changes.
"10 over" means the machinist bores the block/sleeve 0.010" larger than stock. The result is that you have to buy "10 over" pistons and rings to match.
If it was my block, I'd pick the smallest overbore that's required. Leaves some room for next time and the larger the overbore....results in thinner sleeves which isn't great for durability or heat changes.
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Joined: Jan 2008
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From: Florida
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i just bought a used block and i have to get the cylinders bored as there was some rust and light pitting on the sleeves. anyway , the machinst sai they make 3 sizes over stock, 10 over, 20 over and 30 over. im not a mechanic and i dont speak the language so i dont really know for sure what that means. my question is, depending on how much he has to bore, what size piston would i need for each size? thanks in advance.
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