How much needs to be milled for 60cc chambers
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From: Central Valley, CA
How much needs to be milled for 60cc chambers on a set of ported ls6 heads? Does milling the heads affect the way the heads flow or perform? I would like to have a ~60cc chamber to get my compression where I want it with stock head gaskets but I am trying to decide on milling ls6 heads or just going with a set of 5.3 heads to get that bump in compression. It is a california legal car so I am not sure if I would even be able to take advantage of the added flow of the ls6 heads with a stock ls1 intake and shorties with stock cats? Any input is appreciated, thanks.
sounds like my build in my sig lol. anyways would you be putting the 60cc heads on a ls1 shortblock? if so i wouldnt mill them that much because of only being able to get 91 gas out of the pump. but the general rule of thumb is .007 of milling to get 1 cc out of the head. so to get from 64cc to 60cc you would need to mill .028 off of the heads. and yes milling the heads will affect the flow a little bit.
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From: BFE
on a set of ported ls6 heads? Does milling the heads affect the way the heads flow or perform? I would like to have a ~60cc chamber to get my compression where I want it with stock head gaskets but I am trying to decide on milling ls6 heads or just going with a set of 5.3 heads to get that bump in compression. It is a california legal car so I am not sure if I would even be able to take advantage of the added flow of the ls6 heads with a stock ls1 intake and shorties with stock cats? Any input is appreciated, thanks.
So LS6 heads are more beneficial casting. What you have to watch for is not to mill too much and raise your DCR too high to run 91 octane.
So the question is, what cam are you using?
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I was thinking about an EPS 222/226 but on a 115 lsa to help with emissions and possibly on a 113-112 ICL to help raise DCR or going with a little wider split like in the above posts sig which is a 218/230 on a 115+4. I would prefer to have the ls6 heads with standard GM MLS gaskets just to try and keep the cost down and I have heard they are good quality. I would much rather not mill them if I have the option to leave them alone
