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What Is Normal/good Compression For An Rb20det?

esprit

By esprit,
in R Series (R30, R31, R32, R33, R34)

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esprit Proficient

esprit

Posted
Posted

Hey all,

Couldn't find the answer from searching.

What is good compression for a healthy RB20DET engine? A car I'm looking at buying was apparently tested at 150 +/- 4 on all cylinders, is this a good reading? If not what should it be etc etc.

Advice appreciated

Cheers

  • 2 weeks later...
GTRsean Grand Master

GTRsean

Posted
Posted

with an 8.5 to 1 comp ratio and what the manual says, that's pretty good.

warm eng avg should be 161 PSI , limit 128 PSI with no more than 14 PSI difference between cylinders.

dezz Grand Master

dezz

Posted
Posted

when i was looking at getting a 33 locally, i asked some people in the know what compressions were good

they said 170 is perfect (this is RB25DET obviously)

and anything above 140 is still ok...anything like 130-135 or under, and its getting close to rebuild time...

just thought id let you know so you have a rough idea...

they also told me that consistency across all 6 is important as well :(

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