2056 build compression ratio dilema |
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2056 build compression ratio dilema |
jjs3rd914 |
May 8 2018, 08:44 AM
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#1
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Member Group: Members Posts: 124 Joined: 8-August 04 From: Sarasota, FL Member No.: 2,476 |
Building a 2056, want good low end torque and drivability. Car has AC. Targeting 115-125 HP
GA 2L case, stock 2L crank rods, new AA 96mm pistons, biral cylinders New AA 2L heads with 44/36 valves Webcam 086 cam Weber 40IDF dual carbs After numerous searches seem like 8.5 is optimal compression ratio (CR) and the build should get me the targeted HP. BUT finding during assembly, with a deck height of .065" (with .010 barrel spacer) 60 cc head volume which includes 2CC for the piston valve recess, I am only getting 8.1. So option are to leave alone and go with 8.1CR or Machine heads to loose about 6CC or machine barrels to reduce deck height. Was told must use a barrel spacer and am using the thinnest I can find at .010. To get the targetd HP do I need to get to a CR of 8.5, or will 8.1 get me there.? Am really confused about the whole CR optimal number for what I want. Thanks jjs3rd914 |
jjs3rd914 |
May 8 2018, 11:18 AM
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#2
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Member Group: Members Posts: 124 Joined: 8-August 04 From: Sarasota, FL Member No.: 2,476 |
Nditz1
So you have the barrels in the case with no shims, gaskets or whatever they are called. I read somewhere that that is not the way to go. Some shim must be used. Can any of you verify this, if so why? Or does it not make any difference. If I eliminate the .010 shim then that would get me 8.3 CR, Which I might go with. I too not using a head gasket. Still asking members if indeed a CR of 8.5 is optimal for our builds. So would we see driving HP difference if went with 8.1 instead of 8.5. Surely would save me more machining cost's and more time. Machinists seem busier than trying to see your doctor. Thanks jjs3rd914 |
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