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RB26 compression test results High??

sideskyimport#
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sideskyimport# Newbie

sideskyimport#

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Hi, 

Basically as title I have done a compression test on my RB26DETT engine in my 1995 R33 GTR and the results were across all cylinders 200 psi!? This seems high to me as IIRC the owners manual says about 171 psi is what it should be and an average on rb's is around 150-165 and now the car being 24 years old and done 60K miles the results should be that, but mine is 200 psi

This was done on a dead cold engine I should mention and wasn't used for a few days, as I wanted to see the difference between cold and hot.

Can anyone shed some light on why this could be?? Some checks I have done to make sure it's standard engine are as follows

I used a endoscope and the pistons are standard 05U on all 6 a;; pistons are clean on top not carbed up or anything

Checked camshafts back long when I replaced rocker cover gaskets and they seemed like OEM

The car is very standard except exhaust and wheels (normal things) air filters nothing more, all original turbos etc

Only major mod to the car is a Mines ecu it has had since it left Japan 15 years ago, but car is running only .8 bar I'm the third owner since it left Japan and came to the UK

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https://www.sau.com.au/forums/topic/478878-rb26-compression-test-results-high/
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