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whats should the average # be when doing a compression test?

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Old 05-06-2005, 07:28 AM
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Singhg83
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Default whats should the average # be when doing a compression test?

well, im looking at a gsr, and the dealer had run a compression test, and i remeber reading the numbers for the corresponding cylinders - #1 - 162, #2 - 149, #3 - 153, #4 - 160.

are these numbers ok, or can this be a major problem in the long run?
thanks.
Old 05-06-2005, 08:02 AM
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'93TurboD
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Those numbers are very good. Did you try a wet test too? Or is that your wet test?

EDIT: I just noticed that you're looking @ a GSR... 160 across all cylinders is the norm. I think that was a dry test. Try it again with 3 drops of oil in the cylinders and repost. Unless you can't redo it, cyls 2&3 look suspect to me.
Old 05-06-2005, 08:08 AM
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Originally Posted by '93TurboD
Those numbers are very good. Did you try a wet test too? Or is that your wet test?
well, i didnt do it, it was @ the dealership, and they had it on a sheet of maintance that they had done.
Old 05-06-2005, 08:13 AM
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I just noticed that you're looking @ a GSR, sorry. Umm the average comp is 160psi across all cylinders. So cyls 2&3 look suspect to me. It is a fairly high comp. motor. Though, like I said, they could've done a dry test.
Old 05-06-2005, 08:19 AM
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well, how much of a difference would there by between a dry test and a wet test?
Old 05-06-2005, 08:27 AM
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Night and day. A wet test is just a couple drops of oil in each cylinder to help the piston rings seal properly. It would bump cyls 1&4 to the 180's and 2&3 to the 160's easy. You should ask the dealer what compression test they did and go from there.

I personally do them both when I'm doing a comp test. Did they do a leakdown test aswell?
Old 05-06-2005, 08:37 AM
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Originally Posted by '93TurboD
Night and day. A wet test is just a couple drops of oil in each cylinder to help the piston rings seal properly. It would bump cyls 1&4 to the 180's and 2&3 to the 160's easy. You should ask the dealer what compression test they did and go from there.

I personally do them both when I'm doing a comp test. Did they do a leakdown test aswell?
im not too sure if they did a leakdown test on it.
hell im not even sure if im going to go for this car, asking too much money.

but hey thanks alot for answering these questions.

and just out of curiosity, why would the 1 & 4's be higher than the 2&3's?
Old 05-06-2005, 08:46 AM
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Could be a variety of reasons. Piston rings, valve seals, valve seats, carbon buildup and even the dreaded head gasket. A leakdown test would help pinpoint the problem. The numbers in themselves aren't that bad, but if you're buying the car it better be as good as advertised. More than likely the previous owner didn't want to spend the extra $$ on 91 octane gas and pinged the shit out of it. It should run fine, (it is a Honda) but for how long and how hard, I dunno.

Besides it's a GSR, you know you're gonna be revving the shit out of it every chance you get. Hell I do it in my cx, and c'mon, it's a cx, lol.
Old 05-06-2005, 08:50 AM
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hahaha, you never know what true power you have until you own a cx.

well hey dude, thanks for the info, i will find out if they had dont it or not.
Old 05-06-2005, 08:56 AM
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No prob man :thumbup:



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