Compression Ratio
#2
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It is the ratio that the a/f mixture is compressed durring the compression stroke, if your piston had 1 inch of clearance when it was at the top, and went down 4 inches to the bottom, then it would compress the mixture at 4:1.
I believe a stock ls1 is 10.5:1, but I'm not sure, you can calculate it if you know your head chamber size, piston to deck clearance, gasket thickness, stroke, bore and if your piston has a dish you would need that information too.
I think I explained that right, if not someone feel free to correct me or add more.
I believe a stock ls1 is 10.5:1, but I'm not sure, you can calculate it if you know your head chamber size, piston to deck clearance, gasket thickness, stroke, bore and if your piston has a dish you would need that information too.
I think I explained that right, if not someone feel free to correct me or add more.
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Your cam doesn't play into compression ratio, it only controls valve events.
Like itchygomey98 said, post up what head gaskets you used and what kind of stage 2 heads you have (Chamber volume if you know) and someone can tell you what your compression ratio is.
Like itchygomey98 said, post up what head gaskets you used and what kind of stage 2 heads you have (Chamber volume if you know) and someone can tell you what your compression ratio is.
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Originally Posted by term
Your cam doesn't play into compression ratio, it only controls valve events.
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#8
Most of what you guys are wondering has been answered here - https://ls1tech.com/forums/advanced-engineering-tech/111207-ls1-head-combustion-chamber-cc-volume-vs-cr.html
As far as how big of a cam you can use, there is more to consider than just how much total lift and duration the cam has. That is another topic all together. And what 1999_SS_M6 said is correct, what we are talking about here is only static compression ratio.
As far as how big of a cam you can use, there is more to consider than just how much total lift and duration the cam has. That is another topic all together. And what 1999_SS_M6 said is correct, what we are talking about here is only static compression ratio.
#12
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umm, just for the sake of another .02 i like to describe it as :
the relationship between the combustion chamber at bottom dead center to the combustion chamber at top dead center ... alot of folks think that the combustion chamber is just in the head, but anywhere combustion takes place is the combustion chamber ... example, most stock blocks wont have a zero deck height so the small hole that the piston is in will also be figured in as part of the combustion chamber at TDC
the relationship between the combustion chamber at bottom dead center to the combustion chamber at top dead center ... alot of folks think that the combustion chamber is just in the head, but anywhere combustion takes place is the combustion chamber ... example, most stock blocks wont have a zero deck height so the small hole that the piston is in will also be figured in as part of the combustion chamber at TDC
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Originally Posted by term
Your cam doesn't play into compression ratio, it only controls valve events.
Like itchygomey98 said, post up what head gaskets you used and what kind of stage 2 heads you have (Chamber volume if you know) and someone can tell you what your compression ratio is.
Like itchygomey98 said, post up what head gaskets you used and what kind of stage 2 heads you have (Chamber volume if you know) and someone can tell you what your compression ratio is.
#14
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Originally Posted by KingCrapBox
Compression can't begin until the intake valve is closed, so cam choice DOES play a factor in DYNAMIC compression ratio, which is far more important than STATIC compression ratio.
my static compression came out to 12.08 and my DCR to 9.10