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Compression Test Results


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Hey guys got my compression test results on my Rb26DETT as follows.

176 180 177 155 150 170

There is a diff of 30 between cyl 2 and 5 :S Is it worth throwing on some aftermarket turbo's and power fc etc or does it look like rebuild time?

How long do you guys think the engine might last? Seems to run fine? Thanks!

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Hey guys got my compression test results on my Rb26DETT as follows.

176 180 177 155 150 170

There is a diff of 30 between cyl 2 and 5 :S Is it worth throwing on some aftermarket turbo's and power fc etc or does it look like rebuild time?

How long do you guys think the engine might last? Seems to run fine?

Should i get a leakdown test done next? Thanks!

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thats not too bad but depends on whats type of power you are looking to produce.

And i would also suggest getting a leakdown test as this way you will know where you stand and where or what to do

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Yeah, i would prepare for a rebuild... Or sell the car.

If you wont be power figgers now is your chance. I wouldnt push the engine to much, just run factory boost and she will last a little while longer.

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I wouldn't break out the cheque book just yet guys. there are a couple of things that can give incorrect results. I would be happy with 150 in all 6 cylinders as long as it's even. how was the test done? hot? how much time cranking? what type/brand of gauge? how good is the battery? throttle open?

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i wasn't there when the test was done but it was done by a reputable performance shop. I'm getting another compression test and leakdown done on tuesday so when i have the results ill post them up! I doubt the engine could be that bad.. the car is standard and runs very well! nice and smooth good pickup and idles perfect

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I have done compression test on my rb25 and the numbers were 180psi,190psi,180psi,180psi,180psi,190psi, I was surprise with the #, then I went to check the fsm and the fsm says factory is 185 maximum and 150psi is minimum for the motor to be good and a difference (I don't remeber exactly right now) but I think was 15psi between them, so I was really surprised and I've checked to see if I had a rb25de turned to rb25det and my motor is for sure a rb25det not tuned to be a (t) so I went to check my cams and apparently they have been changed (new gasket all around the valve covers,I have to open to see what cams do I have still), so I think the best you to do is, do the compression again this time make sure if you have the battery fully charged no spark no fuel and wide open throttle, turn the ignition for about 5 to 7 seconds and make sure your tester is ok too.

This is what I have done, I'm not 100% sure about rb26 but that is what the fsm says to do for my rb25det.

I hope your motor is ok man!

gl!

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Lower comp on 4 and 5 could even be a head gasket . Test again and do a leakdown to pinpoint the comp loss on 4+5.

Is it a re-built engine or stock? Dont forget carbon built up will increase compression.

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Hey guys well I am happy to report apparently my engine is fine. Wen't and had another compression test done at a very reputable place and also hot and cold leakdown tests done. Compression was 150 on all 6 cyl and on the leakdown just said "nothin to worry about all less than 10%"

I dunno why it came up with dodgy readings the first time but i'm happy with that result!

Cheers

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