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 |
gothspeed |
May 8 2018, 06:53 PM
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#2
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Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
I built a 2056 with 96mm AA valve relief pistons. I had to 'true' all cylinders which got my compression to about 8.6:1 , with a fresh head resurface.
I think you have plenty cylinder material to remove to get to your target. Your valve to piston clearance has plenty of room. As the Web 86 doesn't have big lift. |
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