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Compression Test

ardie

By ardie,
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ardie Experienced

ardie

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Posted (edited)

Hey, i recently purchased a 96 r33 gtst series 2. i just ran a compression test on it the other day and found the readings hovered between 135 - 140 psi. this seems low 2 me cosidering the high compression of the rb25 but i might be wrong. i was just woundering if anybody could shine some light on if this is an issue or are these compressino ratios the expected? any advice would be much appreciated as i am worried that i have purchased a lemon.

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SiR_RB Grand Master

SiR_RB

Posted
Posted
From memory, others have tested lower than this. (from what i've seen on SAU)

140 seems to be the average though. Someone will be able to tell you definately what it should be though.

yer im pretty curious to no wot it is also, u rekon 140psi? around there sumwhere?

ardie Experienced

ardie

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Posted (edited)

ahh that might explain it, last time i did one on my mates VL turbo after a hard drive and i managed 2 burn my hands an impressive number of times, so when i did this it was cold. how would that have affected it? i got the actual readings back and there was only 3 psi variation accross all cylinders

Edited by ardie
wrxhoon Grand Master

wrxhoon

Posted
Posted
ahh that might explain it, last time i did one on my mates VL turbo after a hard drive and i managed 2 burn my hands an impressive number of times, so when i did this it was cold. how would that have affected it? i got the actual readings back and there was only 3 psi variation accross all cylinders

It sounds like you have a healthy engine but your readings are low. Test it again when hot and wot with a good battery and all spark plugs out . You comp gauge maybe wrong too but more than likely the test wasn't done as it should. A leakdown test is a better indication of the condition of the engine .

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