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! |
Twystd1 |
Sep 11 2007, 10:40 PM
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#2
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You don't want to know... really..... Group: Members Posts: 2,514 Joined: 12-September 04 From: Newport Beach, California Member No.: 2,743 |
OK...
Lets assume for a moment that we are using good 1.8 heads. And I can fit larger valves in the heads for no more money if it will be to any advantage. In essence. A 2.0 block, crank, and P&Cs with a WEB 73 cam. Lets also assume about 30 thou deck height. And a basically stock 1.8 pair of heads, with valve train Geo and 911 adjusters. I am guessing that is what 2-OH will end up with. You guys see any problems with that build? If so. What should we look for? Lets also assume factory injection. If so. Will we need to run 2.0 injection? Or will a tweaked 1.8 injection work as well? Note: Exhaust will be factory HEs and a Bursch. NOTE: Carbs are probably not an option because of cost. (else we would be done right now...LOl..) What else ya need as far as ball park data? Clayton |
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