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ey guys,

did a compression test today, however, i disconnnected every hose when i removed the intake manifold and removed all the spark plugs, then i performed the compression test.

Cylinder:

1. 146 PSI

2. 145 PSI

3. 147 PSI

4. 145 PSI

5. 146 PSI

6. 145 PSI

i dunno wat the go is.. And is this the way u do a compression test or not? by removing all park plugs and then cranking it?

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https://www.sau.com.au/forums/topic/146595-compression-test-for-rb20det/
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ok....so keep all plugs in, take one out, test it, then put it back it, then take the next one out and test it yer? do i loost compression when all spark plugs r out? coz i just cranked it till it popped...

Depends on how your gauge reads dude. A lot of low qual gauges about that read way off.

Also rb20 donk is fairly low comp I'd expect 130 - 150.

You look more for variation. The readings on your engine are awesome !!

around 150psi is normal for the age the engine,manual specifies 170psi with the limit value (lowest) 128psi, the variance limit shouldnt be more than 14psi beween cylinders

u should have the engine close to operating temp at least, remove ALL plugs, attach gauge to cylinder (screw fitting is the better ones), depress pedal FULLY u must have WOT, crank till needle stops moving which should be about 7 engine revolutions, then record ur readings,

urs seem good not much variation which is good

im not sure if the readings will be lower or higher when stone cold as i have only done it when at operating temp.

maybe someone can verify that as my engine is not finished yet to be running

cheers,

brad

Edited by RB20/30Det_VL

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