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Discussion Starter #1
Hey guys

Just looking for some opinions on a wet and dry compression test I did on my rb20det, note i did this when the engine was completely cold. Dry test I got around 75psi on all cylinders so I expected with a wet test for it to go up. wet test showed around 78psi on all cylinders.

Does anyone know why I could be getting such even low readings? perhaps its the compression tester? Thanks in advance
 

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Could well be that the valve seal is not good, try the test again with the engine warm and see what you get, I would presume you are keeping the throttle wide open and turning over the engine at least 6 times for each cylinder with a fully charged battery?
 

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Discussion Starter #3
thanks for reply :)

Ill give a warm test a go today then, Yup throttle hard on, cranking about 5-6 times and fully charged battery.
 

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Just replaced all of the turbo set up and that's taken a few days hence me taking so long to reply. So here are all the stats of my compression tests--> These were cold, Dry-76,76,77,76,70,76 Wet all around 78. These were with a warm engine, Dry-77,75,80,75,78,76. Wet, 87,80,90,78,80,80. I noticed fresh oil on spark plug 1 and 3 when pulled out of warm engine and also cylinder 3 was smoking heavily. One would probably assume from this the whole engine is pretty worn-out?
 

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Also It smokes ALOT. at idle it is usually okay and doesn't have much visible smoke but with any revving it just billows smoke out. this could be due to valves as well?
 

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Sounds like it needs a good rebuild, the std figures should be about 100PSI higher than that,
and by those figures, the valve seal is not a big problem, personally, i would either give the whole motor a refresh and forge if you're going for more power.
 

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Discussion Starter #7
Thanks for the input Tricky-Ricky, Ive sourced a new long block :) not yet looking for more power just a road legal rb that doesn't spit clouds
 
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