Compression

1979 CHEVROLET CHEVETTE
28,000 MILES
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09EMDOG
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I am doing a compression test and was wondering what is the compression supposed to be (range) for a 1979 chevy chevette? 4 cylinder
Nov 29, 2011 at 3:30 PM
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HMAC300
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actually anything above 90psi. Normally anywhere from 125-140 psi. But if there is a varianceof 20% on any cylinder you have something wrong, like a valve burnt or something similar.
Nov 29, 2011 at 3:39 PM
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09EMDOG
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so how about 145 or 155? too high?
Nov 29, 2011 at 4:16 PM
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HMAC300
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  • 48,601 POSTS
no that's good. as long as it's not like 145 on one cylinder and 90 on another.
Nov 29, 2011 at 5:04 PM
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