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> 2056 build compression ratio dilema
post May 8 2018, 08:44 AM
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From: Sarasota, FL
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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
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.


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