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Old 05-26-2007, 05:08 AM   #1
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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?
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Old 05-26-2007, 06:57 AM   #2
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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:
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Old 05-26-2007, 09:52 AM   #3
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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 05-26-2007, 09:57 AM   #4
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magic motor
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Old 05-26-2007, 10:21 AM   #5
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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."
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Old 05-26-2007, 11:48 AM   #6
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or maybe it's suckin oil into the CC
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Old 05-26-2007, 11:53 AM   #7
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leak down test, it's the only way.
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Old 05-26-2007, 12:51 PM   #8
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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.
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Old 05-26-2007, 05:59 PM   #9
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Quote:
Originally Posted by y8s View Post
or maybe it's suckin oil into the CC
Bitch, you ever gonna let that go. :gay:
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Old 05-26-2007, 06:19 PM   #10
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Quote:
Originally Posted by olderguy View Post
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:
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Old 05-26-2007, 08:15 PM   #11
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Quote:
Originally Posted by LOLA - 92 View Post
Or -- Massive amounts of Carbon Build-up! :gay:
Now that we have a little more history, I agree.:gay:
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Old 05-26-2007, 08:49 PM   #12
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my compression was 200 across the board.i should let it sipp on some water,but im scared.
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Old 05-26-2007, 08:54 PM   #13
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Quote:
Originally Posted by turbopezz View Post
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.
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Old 05-26-2007, 09:22 PM   #14
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yes,thats what ive been reading..i might do it tonight so no one calls the fire department.
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Old 05-26-2007, 10:53 PM   #15
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Originally Posted by turbopezz View Post
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"
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Old 05-26-2007, 11:23 PM   #16
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Yay fouled plugs and caked 02 sensors.
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Old 05-27-2007, 05:40 AM   #17
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you guys don't like seafoam?
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Old 05-27-2007, 06:13 AM   #18
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Seafoam rules! 160k worth of carbon buildup? hehe

EDIT - And no more mosquitos for the evening! =)
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Old 05-27-2007, 07:22 AM   #19
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Quote:
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you guys don't like seafoam?
It's not that I don't like SEAFOAM --- I like the idea of FREE WATER. :gay:
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Old 05-27-2007, 04:58 PM   #20
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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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