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compression test
Posted: Tue Mar 10, 2015 7:50 pm
by 208ss
Just did a test and all read 120. Is this a cause for concern. I thought it should be around 140-160
Re: compression test
Posted: Tue Mar 10, 2015 8:34 pm
by Alphius
What's your elevation? Engine warm or cold? Was the throttle plate fully open when you were doing your test? At sea level on a warm engine with the throttle open I'd expect 140+ out of a turbo Subaru.
Re: compression test
Posted: Tue Mar 10, 2015 8:53 pm
by 208ss
I'm at 2800 feet. Engine was warmish let it cool for about 30 mins. Did not push the throttle when cranking.
Re: compression test
Posted: Tue Mar 10, 2015 11:00 pm
by Alphius
Your altitude compensation factor is around .92. If all of your cylinders were around 120 with not much variance then I think your engine is healthy. Opening the throttle usually gives a 10-20% increase in numbers, which combined with your altitude compensation means you are well within the range I consider good.
Re: compression test
Posted: Tue Mar 10, 2015 11:09 pm
by 208ss
Ok thank you