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hallo.

just bought an '89 gtr a few weeks ago, did an engine compression test, and its averaging about 142-145 accross all 6 cylinders. not exactly an impressive figure, but before i do anything in the means of modifications to the car, i wanna get it running the way it should do.

self admitedly not the guru with cars, so i've come to this forum for some help/suggestions.

- without looking at it, what are the usual causes of a below 'acceptable' engine pressure? I know that a decent platform to work from is the 160 mark, is that right?

- what can be done to improve the engine pressure, along with rough price estimates.

i know i have given limited solid information,so if there's anything else that would help you guys answer my query, then lemme know.

cheers for you time.

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You see if only one or two were down you could blame a head gasket but if all 6 are evenish with in 5-7 psi of each other then sorry but yeah time for a rebuild....

If the oil does not improve this result then id try another gadge... Also look to see that the timing is correct....

any body :| ?

if the figures are only 2-3psi different across all cylinders i would not worry at all, this is the main thing u judge compression by, there are many factors that can stuff around your outright figure so dont worry about that.

i would think your motor is in good condition. if there was say 10-15psi differences then thats a different story.

do a leakdown test if you really want to be sure.

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