Compression Check #s, do these sounds about right?
Thread Starter
Burning Brakes
Joined: Feb 2003
Posts: 1,212
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From: OH
Compression Check #s, do these sounds about right?
Just did a compression check while everything was apart. Got 160-165 on all the cylinders. Is this about right for a 85 with 68K miles on it?
Oh some more information, engine has been cold, hasn't run in 4 weeks. And I didn't prop the throttle blades open, just read that you should probably do that, oh well, guess the numbers might be a little lower then if it was wide-open?
[Modified by rsafier, 3:19 PM 3/14/2004]
Oh some more information, engine has been cold, hasn't run in 4 weeks. And I didn't prop the throttle blades open, just read that you should probably do that, oh well, guess the numbers might be a little lower then if it was wide-open?
[Modified by rsafier, 3:19 PM 3/14/2004]
Race Director
Joined: Sep 2000
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From: The Top of Utah
Re: Compression Check #s, do these sounds about right? (rsafier)
What you show looks good, but you should really retest with the throttle open. All cylinders within 10% is a fairly universal standard. These numbers don't even come close to the limits. Believe it or not, cam timing has a bigger influence on static compression numbers than compression ratio. My 1984, with 160,000 mile on it, and never been apart, varies between 165 and 175. It also has a 9.0:1 compression ratio.
RACE ON!!!
PS. The numbers will be higher with the throttle open.
RACE ON!!!
PS. The numbers will be higher with the throttle open.
