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ICD ICD is online now
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Are these compression numbers OK?

140 on five cylinders, 150 on the 6th. Is this OK? What is the acceptable range?

How is a 6 - 8% leak down test on all cylinders. Is that OK?

Old 07-26-2004, 11:49 AM
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don't know about leak down but your compression numbers are just fine. They should be within 10%
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Old 07-26-2004, 11:55 AM
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Both are good.
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Yellow 77 Sunroof Coupe/cork interior; 3.2L SS '80 engine/10.3:1/No O2; Carrera Tensioners; 11 Blade Fan; Turbo tie rods; Bilstein B6; 28 tube Cooler; SSI, Dansk; MSD/Blaster; 16x7" Fuchs/205/50 Firestone Firehawk Indy 500s; PCA/UCR, MID9
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Old 07-26-2004, 11:57 AM
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On a leakdown, ideal is less than 5%, over 5% and something is showing some wear.
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Old 07-26-2004, 11:57 AM
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I was just about to edit my response when Kurt logged in. 5% or less is best. How many miles on the engine? If you have 100k or more, I think 5-8% is to be expected.
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Yellow 77 Sunroof Coupe/cork interior; 3.2L SS '80 engine/10.3:1/No O2; Carrera Tensioners; 11 Blade Fan; Turbo tie rods; Bilstein B6; 28 tube Cooler; SSI, Dansk; MSD/Blaster; 16x7" Fuchs/205/50 Firestone Firehawk Indy 500s; PCA/UCR, MID9
Never leave well enough alone
Old 07-26-2004, 12:04 PM
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ICD,

Where are you located? Altitude makes a large difference in compression measurement.

Kurt, Tim, and Paul are right on.

Everyone should record these measurements on a regular basis for a baseline for your engine. How do you know you have, or are developing, a problem if you don’t know the history?

Best,
Grady
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Old 07-26-2004, 12:12 PM
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The car in question is an '87 Carrera. The car is in Kansas City. It has 115k on it., but it had a valve job around 55K.

The bottom line question is this:

Will this car need valves or rings any time soon with these test results?
Old 07-26-2004, 01:06 PM
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No guarantees, but probably no.

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Old 07-26-2004, 01:08 PM
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