 Compression ratio, Whats the max CP differance |
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| DavidSweden |
 Jan 19 2021, 03:47 PM
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Member  Group: Members Posts: 479 Joined: 8-June 14 From: Sweden Member No.: 17,452 Region Association: Scandinavia  |
Hello,
What is the maximum allowable compression ratio difference between cylinders? 2056 motor AA big bore Thanks in advance |
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| DavidSweden |
Jan 20 2021, 10:39 AM
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Member Group: Members Posts: 479 Joined: 8-June 14 From: Sweden Member No.: 17,452 Region Association: Scandinavia |
I am installing some new heads because of damage to one of the spark plug holes and at the same time installing a 2056 AA piston & cylinder set. The engine is a stock 2.0 (stock cam) with D jet
The new heads have been fly cut at some time- cylinder 1 & 2 = 59cc and 3 & 4 = 57cc. Deck height = 1.2mm on all cylinders, and the AA piston valve cut outs = 7cc. This gives a compression ratio of 7.84:1 on cylinders 3 & 4 and 8.03:1 on cylinders 1 & 2 This is with no shims and no head gasket, so unless I get the cylinders or heads machined I am stuck with these low compression values. The compression ratios on each side of the engine are different I guess this is ok but I just want someone who knows to give me an opinion. Thanks in advance |
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Posts in this topic
DavidSweden Compression ratio Jan 19 2021, 03:47 PM
rfinegan I believe under 50 to 60 psi will have problems an... Jan 19 2021, 03:57 PM Jake Raby What values are you seeing? Are you performing ng ... Jan 19 2021, 09:40 PM rfinegan what does the work out as far as % error on your C... Jan 20 2021, 11:14 AM rfinegan that is pretty low compression ratios Jan 20 2021, 11:15 AM
Dave_Darling
that is pretty low compression ratios
Not for a... Jan 21 2021, 04:53 PM stownsen914 If I read your post right, wouldn't the fix be... Jan 22 2021, 11:35 AM Jake Raby I thought you were trying to get a value for a com... Jan 20 2021, 03:00 PM DavidSweden
I thought you were trying to get a value for a co... Jan 20 2021, 03:20 PM rfinegan I have read a lot of the AA cylinders have to be t... Jan 20 2021, 03:37 PM |
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