Dynamic Compression Ratio Post ???
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Joined: Sep 2000
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From: The Top of Utah
Dynamic Compression Ratio Post ???
Some time ago, in the not too distant past, a link was posted to a calculator for calculating dynamic compression ratio (dcr). I downloaded that calculator, and know my dcr. However, there were also guidelines as to what was safe or reasonable for specified applications. Can anyone recall or direct me to those guidelines? I am interested in installing a smaller cam, but I am afraid I can't go much smaller.
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From: Indianapolis IN
Re: Dynamic Compression Ratio Post ??? (CFI-EFI)
Heres one I use, may not be the one you are looking for! http://www.empirenet.com/pkelley2/DynamicCR.html
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From: The Top of Utah
Re: Dynamic Compression Ratio Post ??? (ld85)
That is EXACTLY the site I was looking for. When I first went there, I down loaded the calculation program, unzipped it and have it on my hard drive, but his dissertation isn't there. Thanks to you, I have now down loaded the whole page, and I can finally make some sense of my numbers. It looks like I have a LOT of room for the smaller cam, that I think I need. Thanks, and...
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Le Mans Master
Joined: Mar 1999
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From: delmont pa
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Re: Dynamic Compression Ratio Post ??? (CFI-EFI)
without a knock sensor in your engine i do not know how you would know for sure if this theory works. :chevy
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Re: Dynamic Compression Ratio Post ??? (clem zahrobsky)
I think it is more than just "theory". Possibly, the exact DCR ratio tolerences for different gasolines vary for different engines and conditions. Currently, I am way below the 8.3 street/premium limit. I feel I will be better served by a smaller cam, and it appears my engine combination will allow it. By the way '84's came with knock sensors.
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Le Mans Master
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From: delmont pa
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Re: Dynamic Compression Ratio Post ??? (CFI-EFI)
a lot of things enter into this,fuel ditribution,temp,deposits in the chamber,sharp edges and even excess oil in the combustion chamber. :chevy
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From: The Top of Utah
Re: Dynamic Compression Ratio Post ??? (clem zahrobsky)
I don't argue with any of that. This is a new engine I purchased. I have disassembled it to inspect and reassemble so *I* know how it is put together. There are no sharp edges, no carbon, oil is expected to be minimal, and operating temps will have to be determined. I have had the block decked (yes, on a new engine) and raised the cr, slightly. I have long felt the cam was too "big" and the dcr numbers prove it. Any/all guidence is welcome, but meanwhile I'm looking for a smaller cam. Thank you for your interest and concern.
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