# Normal compression for SR20DET



## AyrtonSennaD (Jun 10, 2002)

What is the normal compression for the SR20DET??


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## Sr20 B12 (May 1, 2002)

I belive you have a Bluebird engine (as from your posts on sr20deforum.com) so it's 8:5:1.

-Mario


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## Guest (Aug 27, 2002)

I may have misunderstood, but I thought has was asking for cylinder compression, not the overall compression ratio. I'm not 100% positive about this, but I believe with a DET, 140 psi across the board is normal.


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## Sr20 B12 (May 1, 2002)

Zak91SE-R said:


> *I may have misunderstood, but I thought has was asking for cylinder compression......*


You know, I though he ment that, but I was trying to be a smart ass. I've heard anything under 135psi is bad compression.


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## UnderDog (Jul 14, 2002)

140 is about right. I saw some combustion chamber PSI figures from a guy with an NX2000 with an SR20VET in it. Maybe you guys know who I'm talking about. Anyway, his numbers ran anywhere from 140 to 145.


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## AyrtonSennaD (Jun 10, 2002)

Thanks guys. But i got really bad compression. It's like 100 PSI per cylinder. What sould i do

Help please


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## boost_boy (May 25, 2002)

Stock Sr20DET compression should be around 170psi (highest) and 130ish/140is as long as each cylinder is within 5% of each other and even so this is the result of a worn engine. Do you have individual cylinder figures? Would help better determine what happened. I bet #2 is the weaker of the bunch...could be wrong though.


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