low compression number in 1 cylinder

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twowheeled
Posts: 28
Joined: Sun Nov 29, 2009 5:31 pm

low compression number in 1 cylinder

Post by twowheeled »

I've been getting ready to do my turbo install on my 2007 NC. Today I did a compression test and to my dismay, cylinder 4 is low. It is giving 188psi and the others are all around 200psi. With some engine oil in there it went up to 200psi. However putting some engine oil in cylinder one made it go from 200 to 230psi. I'm not really sure what to do at this point. Boost it anyways? :? The engine has 25k on it, and I did my best to break it in properly when new.
Brian
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Re: low compression number in 1 cylinder

Post by Brian »

Yes, boost it anyways. That's normal variation for a production motor with some use on it. My number 4 cylinder is similar.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
twowheeled
Posts: 28
Joined: Sun Nov 29, 2009 5:31 pm

Re: low compression number in 1 cylinder

Post by twowheeled »

gotcha... alright stand back everybody! :lol:
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