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Compression test results

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Old May 26, 2007 | 04:08 AM
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Default Compression test results

So last night I got a ride in my friend's 1990 red miata. It was a blast and I fell in love with the little car - first convertible I was ever in!

We did a compression test later that night and the motor came out with 215psi compression across the board. The manual specifies 192psi compression and the tester was working fine. The motor has 160k miles on it. Has anyone seen such high compression on a broken in motor?
Old May 26, 2007 | 05:57 AM
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Sounds like someone shaved the head, used a thinner head gasket, or changed pistons along the way if the test was done correctly. But that's just my guess:gay:
Old May 26, 2007 | 08:52 AM
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yeah a motor I had came back at 205 psi per hole. I figured that my gauge may be a bit innacurate.... and hope that I didn't sell some bad *** built motor for $350.
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Old May 26, 2007 | 08:57 AM
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magic motor
Old May 26, 2007 | 09:21 AM
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It shouldn't do it that much, but if it was owned by someone who rarely took the car above 4k rpm (as some "wine & cheesers" may be known to do), carbon buildup could also certainly raise compression as well. Time to do the fabled "ferrari tune-up."
Old May 26, 2007 | 10:48 AM
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or maybe it's suckin oil into the CC
Old May 26, 2007 | 10:53 AM
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leak down test, it's the only way.
Old May 26, 2007 | 11:51 AM
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we'll have to look into it some more, I don't think it's burning any oil and I don't think the motor was ever opened up but then again we don't know the complete history. It runs fairly well however.
Old May 26, 2007 | 04:59 PM
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Originally Posted by y8s
or maybe it's suckin oil into the CC
Bitch, you ever gonna let that go. :gay:
Old May 26, 2007 | 05:19 PM
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Originally Posted by olderguy
Sounds like someone shaved the head, used a thinner head gasket, or changed pistons along the way if the test was done correctly. But that's just my guess:gay:
Or -- Massive amounts of Carbon Build-up! :gay:
Old May 26, 2007 | 07:15 PM
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Originally Posted by LOLA - 92
Or -- Massive amounts of Carbon Build-up! :gay:
Now that we have a little more history, I agree.:gay:
Old May 26, 2007 | 07:49 PM
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my compression was 200 across the board.i should let it sipp on some water,but im scared.
Old May 26, 2007 | 07:54 PM
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Originally Posted by turbopezz
my compression was 200 across the board.i should let it sipp on some water,but im scared.
The key is to let it sip, not gulp.
Old May 26, 2007 | 08:22 PM
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yes,thats what ive been reading..i might do it tonight so no one calls the fire department.
Old May 26, 2007 | 09:53 PM
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Originally Posted by turbopezz
yes,thats what ive been reading..i might do it tonight so no one calls the fire department.
Water is not bad! It's that other **** they use over on m.net that makes the black smoke.........:gay: "SEAFOAM"
Old May 26, 2007 | 10:23 PM
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Yay fouled plugs and caked 02 sensors.
Old May 27, 2007 | 04:40 AM
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you guys don't like seafoam?
Old May 27, 2007 | 05:13 AM
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Seafoam rules! 160k worth of carbon buildup? hehe

EDIT - And no more mosquitos for the evening! =)
Old May 27, 2007 | 06:22 AM
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Originally Posted by Lex
you guys don't like seafoam?
It's not that I don't like SEAFOAM --- I like the idea of FREE WATER. :gay:
Old May 27, 2007 | 03:58 PM
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i let my car sip a very very little bit of water ..and you can actually here a difference the motor sounds a little smoother quiter.



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