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Is this engine compression okay ??

Hey guys did a engine compression test on my engine and got the following results.

1# 135psi
2# 140psi
3# 130psi
4# 135psi
5# 135psi
6# 130psi

 

The car is a 1998 r34 gtt, is this compression okay for the car ??

The only performance work i intend on doing to the car, is a tune with the stock turbo.

Edited by ruinned
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Make sure you get it with the feature pack.

Gives you option of full flex support by feeding the 0-5V into the diagnostic port. Not to mention anti-lag for launch, great for showing who's boss lol.

You can also check the variance between cold engine dry compression and engine warm wet compression values to guage the health of the piston rings and valve train

From another forum;

a dry test is just how the engine runs and it will tell you only the compression. A wet test is done after with oil in the cylinders, in this "SECOND" test if the numbers go up you will know it is the rings and if the numbers stay the same all is well.

IE dry test on cyl 2 was 30 lbs low and wet the reading was back up to par it is the rings. If the "SECOND" test was still at 30 lbs low it would be in the valve train (valve adjustment) or a sticky/leaky valve.

17 minutes ago, squareznboxez said:

You can also check the variance between cold engine dry compression and engine warm wet compression values to guage the health of the piston rings and valve train

From another forum;

a dry test is just how the engine runs and it will tell you only the compression. A wet test is done after with oil in the cylinders, in this "SECOND" test if the numbers go up you will know it is the rings and if the numbers stay the same all is well.

IE dry test on cyl 2 was 30 lbs low and wet the reading was back up to par it is the rings. If the "SECOND" test was still at 30 lbs low it would be in the valve train (valve adjustment) or a sticky/leaky valve.

Cheers for the information, i will prob do a wet test this weekend and see if the results are different.

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