Compression test...what do these numbers mean?

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Jul 23, 2007 | 03:04 AM

Hemi Killer

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From: Bossier City, LA

Compression test...what do these numbers mean?

Here's the results. I turned the motor/starter over 4 times for each one. I did it cold, engine hadn't been cranked in a day.

Cylinder #1.....210
Cylinder #2.....202
Cylinder #3.....212
Cylinder #4.....210
Cylinder #5.....205
Cylinder #6.....210
Cylinder #7.....220
Cylinder #8.....195

I was suprised that the #7 cylinder was high. Does this look okay so far? Is 195 kinda low for the #8 cylinder?

Last edited by Hemi Killer; Jul 23, 2007 at 09:12 PM.

Jul 23, 2007 | 04:10 AM

PREDATOR-Z

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From: BFE

yeap, real good so far

Jul 23, 2007 | 06:14 AM

brad8266

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From: Watertown, NY

looks really good man.

Jul 23, 2007 | 07:57 AM

carrsls1_camaro

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From my exp you will find that 5,7,6,and 8 will be alittle bit higher than the front 4.

Jul 23, 2007 | 12:54 PM

heavymetals

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From: Southern Calif.

Looks very good.

You have almost a less then 5% variance.

Jul 23, 2007 | 01:47 PM

bczee

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From: Concord, CA

You always want to see it with no more than 10% variance between the High and Low findings, but 5% is good.

Another good test is to use a Leak Down tester. That will tell you more information on the health of the rings and valves vs static compression.

What is your objective on doing this test ?...