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, 09:05 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 |
We need solutions. Not bagging on the previous builders and machining. Whats done is done.
And thanks Jake for the notion of the bus pistons. Hadn't thought of that. Thats another solid possibilty. Does ANYONE know if a 2.0 with 1.7 injection and a web injection cam can be made to work properly with a factory 1.7 injection system? (And I sniff the answer is no. In truth., I don't know) Thats the next stumbling block. OR if we use the pistons Jake suggests. Can the 1.7 injection be used? This is out of my element. I try to play with stock injection as little as possible. And we have very little bucks (ZIP) to get this done. Thats the fun part. Do it right for nada. Just have to figure out how. What the hell. You guys have any more ideas. Any trades? Whatch think? And give us only solutions. We know the problems. Can't cry over spilled milk. That will get us nowhere. We need solutions...!!!!!!!!!!!!!!!!!!!!!! I haven't seen this engine yet to measure anything. That should be interesting as well. Lets see what we can do fellas. Apparently pictures to follow as soon as the heads come off. I'll be gone for few days. I am going up on a hill with a thousand men and having a little BBQ with my friends. Gunna be cooking wild game from all over the world. And I have to make sure it goes off impeccably. Catch ya Saturday.... Regards, Clayton |
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