Compression Ratio, Too High...Too Low ??? |
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Compression Ratio, Too High...Too Low ??? |
2-OH! |
Sep 6 2007, 05:44 PM
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#1
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Senior Member Group: Members Posts: 552 Joined: 17-October 03 From: Santa Clarita, Kalifornication Member No.: 1,253 |
Ok folks,
We just finished rebuilding the motor...94mm pistons and cylinders to match...71mm stroke...but old 1.7 case...CC'd the heads and come up with 44 cc's per cylinder... Do the calculations and we come out with 1971 cc's...Great !!! But, The problem is the compression ratio is now 10.64 to 1... The question of the day: Should I take the cylinders and heads back off and shim them to get a little relief...Probably not going to get much...Might knock it down to 10 or 9.75 (if I'm lucky)... DO NOT want this thing to clatter and diesel on me when I get it back together... OK, let me have it...What are your thoughts ??? 2-OH! |
2-OH! |
Sep 6 2007, 09:43 PM
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#2
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Senior Member Group: Members Posts: 552 Joined: 17-October 03 From: Santa Clarita, Kalifornication Member No.: 1,253 |
I agree with Aaron above...
Somebody check my math... Can someone give me a formula for determining the compression ratio...Here is what I used without my formula so I can get an unbiased opinion... Heads cc = 44cc Stroke = 71 mm = Height Cyl. Dia = 94 mm = divide by two for Radius Formula ??? mm to cm conversion... 1mm = .1cm Pistons do hve a very slight dish, but are really almost flat... 2-OH! |
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