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Compression Test Difference

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Old Feb 18, 2019, 05:02 AM
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NP
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Compression Test Difference

I have a noobish question regarding compression test results. Several months ago one of my valves decided to let go which caused compression issues in one of the cylinders - compression test results were 180 across except for the one, which was 0.

Had the same reputable evo shop do the work to fix it, valve job, HG, headstuds, timing belt, etc.. they put together and tuned my 2.4 setup in the past. Got the car back and did another compression test, result: 160 - 155 - 160 -155. Using the same compression tester.

What would cause this much of a difference in compression readings? Headgasket? The shop used a cometic 87mm HG (previous was - oem HG bored over).
Old Feb 18, 2019, 11:34 AM
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If your running cams it will effect your readings.
Old Feb 18, 2019, 11:47 AM
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Probably different head gasket thickness. I wouldn't worry about it.
Old Feb 18, 2019, 01:12 PM
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Originally Posted by wht95scort
If your running cams it will effect your readings.
Same aftermarket cams. Good to know though.
Old Feb 18, 2019, 01:14 PM
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Originally Posted by letsgetthisdone
Probably different head gasket thickness. I wouldn't worry about it.
I figured it may have something to do with the HG difference. Thanks!
Old Feb 18, 2019, 04:19 PM
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Drive it




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