 2056 build compression ratio dilema |
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| jjs3rd914 |
 May 8 2018, 08:44 AM
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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 |
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Posts in this topic
jjs3rd914 2056 build compression ratio dilema May 8 2018, 08:44 AM
nditiz1 I was running into the same issue. I'm not su... May 8 2018, 09:27 AM jjs3rd914 Nditz1
So you have the barrels in the case with n... May 8 2018, 11:18 AM ConeDodger You can go higher. 9-9.5:1 May 8 2018, 11:29 AM nditiz1 Conedodger is correct you can go higher.
The dile... May 8 2018, 12:01 PM Mblizzard I have used this spreadsheet to play with the numb... May 8 2018, 02:32 PM McMark You're not going to get where you want with 8.... May 8 2018, 05:02 PM
jjs3rd914
You're not going to get where you want with 8... May 8 2018, 06:52 PM Vacca Rabite Are you using a head gasket?
If so - don't. T... May 8 2018, 06:41 PM gothspeed I built a 2056 with 96mm AA valve relief pistons. ... May 8 2018, 06:53 PM Geezer914 I thought the piston valve relief was 7cc's? ... Jan 13 2021, 01:53 PM VaccaRabite
I thought the piston valve relief was 7cc's? ... Jan 14 2021, 08:02 AM Geezer914
I thought the piston valve relief was 7cc's?... Jan 14 2021, 08:33 AM Jake Raby This is where a mock up of components up front com... Jan 18 2021, 11:52 PM  |
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