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rb25de s2 compression numbers

C.callander
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C.callander Apprentice

C.callander

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hey guys i recently done a engine swap on my r33 and i did a compression test its a rb25de s2 and got these scores (all in psi) 1-160 2-165 3-155 4-155 5-160 6-155 so a average score of 158psi, and my question to you is this good compression for a rb25de engine, all googling give me information on rb25dets so no use to me as turbos are normally lower compression the non turbo's. 

cheers cameron

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Duncan Grand Master

Duncan

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Posted

Given how many variables there are in compression tests (the gauge, the seal, battery voltage, was the throttle wide open, how long did you crank etc etc), and also that engines almost never fail evenly (even when it is just ring wear), the important thing in a compression test is reasonably even results, which you have.

Time for skids.

C.callander Apprentice

C.callander

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Hey man i had a fully charged battery throttle wide open and i cranked the car six times per cylinder yea its not all even results theres a 10psi variable from low to high which is ok yea was just seeing if its acceptable compression for a na that might get the cheeky turbo later 

Ben C34 Grand Master

Ben C34

Posted
Posted

If you answer yes to both questions pull engine out and rebuild it

 

Does it smoke or rattle?

Do you want to rebuild it?

 

 

Otherwise leave it alone. Thrash it. If it breaks it was shit and you didn't want it. Simple stuff mate. Don't overthink it.

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