For those of you that are dealing with Evos everyday,

I decided to do a compression pressure test to see the health of the valvetrain, gaskets, etc.

I am looking to get the more experienced guys on Evos to comment if this results are normal or whatever case may be. I followed the instructions on the manual: Warm car at normal temp, remove cables and plugs, remove crankshaft sensor and WOT during the test. Per manual, normal pressure should be 1128-951 kPa or 163-138 PSI.

Note: I used the compression tester that you find at PepBoys! FWIW!

These are my results:

Piston 1:



Piston 2:



Piston 3:



Piston 4:

 

nice

 

Seems that piston 1 is like in the bottom of the tolerance per manual. I do not think that the tester itself is a little off. It sits below the 0 mark.

dxbevo9.... I think that you mean that the numbers are looking OK! Right?

 

Did you follow step #1?

1. Before inspection, check that the engine oil, starter and
battery are normal. Also, set the vehicle to the following
conditions:
• Engine coolant temperature: 80 − 95°C (176 − 203°F)
• Lights, and all accessories: OFF
• Transaxle: Neutral

 

Yes! I followed that! I am using the mini battery and I think that the cranking was a little slow comparing to a bigger higher amp battery.

I left the engine to reach max temp. It was running for like 10 minutes and a 83 degrees ambient temp.

 

Hey joedr, the spec for Evo IX compression measurement is 92-145 psi. The cylinder to cylinder max variance is 14 psi. The numbers you have are for an Evo VIII.

 

Thanks for the info mrfred!

I though they were the same and the manual I have is in fact for the VIII.

So, I guess that I am good to go then!

 

FWIW on my 05mr, with 280 cams, it was 145 all the way across the board.

 

Hmm.... Just to throw it out there, my stock 4g64 read 185-190 across all 4 cylinders. I don't think I'm supposed to have that much higher a compression ratio, like 9 to 1 stock. And I have the exact gauge as in the picture, only from advanced auto.

I did buy a straight pipe that screwed into the cylinder, I didnt' think I could get the flimsy hose to screw in completely.

 

yes bro i meant they look good.....they are very consistant!

 

I guess that based on the actual specs for the IX (Thanks mrfred), seems to be in pretty good shape then.

 

Looks fine to me, esp considering the PP gauge. :-)