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Compression Test Results

Old Apr 13, 2008 | 07:17 PM
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Default Compression Test Results

These are the results of the compression test that I did yesterday for my lq4 swap. The lq4 for the most part is stock other than the cam...I replaced all the bearings and rings and these were the results.

1 - 175psi 2 - 180psi
3 - 187psi 4 - 180psi
5 - 185psi 6 - 185psi
7 - 162psi 8 - 160psi

I called my engine guy after i did the test and read him the results and he basically said if it was his motor he would run it. He wasnt real worried about the two low readings. He just said run it for 15-20 min at idle, drain the oil and then run it again on the road for 100 or so miles and recheck the compression after the second oil change and it should be better.

Anyone wanna share some imput?
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Old Apr 13, 2008 | 07:23 PM
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highest to lowest shouldnt be any more then 10-12 off
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Old Apr 13, 2008 | 07:35 PM
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I'd do just what he recommends. Those aren't that bad off and will probably seal up after a few miles.
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Old Apr 13, 2008 | 07:55 PM
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i had 1 at 115 some from 140 to 155 and the rest were 175-180 on my 6.0..i rebuilt it
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Old Apr 13, 2008 | 08:03 PM
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run it and let the rings seat in good and check it again, should get better results...IMO
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Old Apr 13, 2008 | 09:21 PM
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do a wet test and see if the number comes up?
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Old Apr 13, 2008 | 09:32 PM
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if this is a brand new motor man clam down and put some miles on it.
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Old Apr 14, 2008 | 09:44 AM
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yeah i am not real conserned about the lower numbers until after i run it. It is dry (other than assembly lube) right now so i will re-test it after i run it wet and put some miles on it
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Old Apr 14, 2008 | 11:36 AM
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I did not see it was new...the rings just need to seat a bit.
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Old Apr 14, 2008 | 12:15 PM
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Just give it some time bro!
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