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Compression Test Results

koduRB25det

By koduRB25det,
in General Maintenance

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Samon Proficient

Samon

Posted
Posted
to day i did compression test for my rb25 det. its 1993 s II, 87000 km on it.

1 - 110

2 - 110

3 - 120

4- 110

5 - 120

6 - 120

if some body can say something abt this...please. im bit worry abt this

That doesn't sound too bad to me... IIRC my RB25DE (before I turboed it) read around 190PSI across the board, but I think my gauge may be reading a little high. The DET version will always have lower compression (to prevent detonation with boost)

The most important thing is that the compression is fairly even across the board. If there's one or two cylinders which are much lower than the rest, it's a good indication you've got problems.

When I broke the ring lands I had about 190PSI in the good cylinders and about 60 or so in the dead ones... I wouldn't think you've got anything to worry about.

koduRB25det Community Regular

koduRB25det

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  • Author
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according to rb25det nissan specs min is 130 psi and max 175 psi. and the ratio s/b 9.0 thats why i worried. i have used T&E Compression tool for test. thx any way

That doesn't sound too bad to me... IIRC my RB25DE (before I turboed it) read around 190PSI across the board, but I think my gauge may be reading a little high. The DET version will always have lower compression (to prevent detonation with boost)

The most important thing is that the compression is fairly even across the board. If there's one or two cylinders which are much lower than the rest, it's a good indication you've got problems.

When I broke the ring lands I had about 190PSI in the good cylinders and about 60 or so in the dead ones... I wouldn't think you've got anything to worry about.

koduRB25det Community Regular

koduRB25det

Posted
  • Author
Posted

coz rb25det factory specs says it s/b min 130 psi and max 175 and the ratio will be 9.0. thats why... i have used T&E Compression tool. thx any way.

looks a bit lowish from memory?

I dont have a rb25 whats it sposed to be , you have one an all!

seems relativly even what sorta gauge you using ?

do you know its accurate?

why you worried?

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