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Compression test #'s

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Old Oct 14, 2007 | 07:37 PM
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Default Compression test #'s

Well i did a compression test today, i admit my oil adding on the wet test was not consistant at all, so i'm not trusting those numbers much at all.. but anyways, heres how it went, tell me what you think:

DRY / WET

#1 191/194
#2 192/195
#3 187/210
#4 212/225

I also have another major problem, but ill start a new thread for it
Old Oct 14, 2007 | 08:42 PM
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looks fine to me.
Old Oct 14, 2007 | 09:28 PM
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Kinda weird how cyl 4 is so much higher than the rest.
Did you hold the throttle to the floor? Judging by your numbers you did, it makes a pretty big difference.
Old Oct 14, 2007 | 09:34 PM
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Err what's all this 'dry/wet' business about ?
Old Oct 14, 2007 | 10:16 PM
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Originally Posted by cjernigan
Kinda weird how cyl 4 is so much higher than the rest.
Did you hold the throttle to the floor? Judging by your numbers you did, it makes a pretty big difference.
Yeah i thought the same thing, and yeah it was held to the floor
Old Oct 15, 2007 | 12:06 AM
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Originally Posted by Fergus
Err what's all this 'dry/wet' business about ?
dry is dry and wet is adding a teaspoon of oil or so through the spark plug hole onto the top of the piston to seal any leaks the rings may have. If the compression goes up it can help determine where you're having leaks.
Old Oct 15, 2007 | 12:36 AM
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I also did a compression test today to just see where my motor was at (no wet test) and got:
175
175
175
185

My cylinder 4 is also a bit higher for whatever reason. Last time I compression tested at 1k miles on the new build I saw 210 on every cylinder but I think that gauge must have read high for some reason. Engine was also at full temp while this time the engine had cooled for 15 minutes or so.
Old Oct 15, 2007 | 01:17 AM
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Originally Posted by johndoe
dry is dry and wet is adding a teaspoon of oil or so through the spark plug hole onto the top of the piston to seal any leaks the rings may have. If the compression goes up it can help determine where you're having leaks.
Thanks.
I learnt something new today
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