Maximum milling on LM4/LM7 862 Heads
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Maximum milling on LM4/LM7 862 Heads
Hey guys,
I am looking at increasing my CR on my stock LM4 and was wondering what the max amount I can mill off of the 862 heads. I am hoping to get into the 11:1 range if possible. I also have a 224/224 .581/.581 114LSA cam and springs going in at the same time. Thanks!
I am looking at increasing my CR on my stock LM4 and was wondering what the max amount I can mill off of the 862 heads. I am hoping to get into the 11:1 range if possible. I also have a 224/224 .581/.581 114LSA cam and springs going in at the same time. Thanks!
#2
LM4 has flat top pistons I'm 95% sure
Just mill the head .03 and your at 11:1 compression with stock height .051 gaskets. I would not milled heads more than this! some people will mill a max of .04 on 243s
Your piston to valve clearance should be fine but I would defiantly do some research to make sure b/c of the flat tops.
You will need to order a push rod length checker if you mill the heads. All blocks can be different so don't listen to somebody that tells you the "proper length" check for your self.
Should be around a 7.375 but like I said check!
Just mill the head .03 and your at 11:1 compression with stock height .051 gaskets. I would not milled heads more than this! some people will mill a max of .04 on 243s
Your piston to valve clearance should be fine but I would defiantly do some research to make sure b/c of the flat tops.
You will need to order a push rod length checker if you mill the heads. All blocks can be different so don't listen to somebody that tells you the "proper length" check for your self.
Should be around a 7.375 but like I said check!
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