Compression Test

[pitbull]

Anyone know what the engine compression is supposed to be in these cars? I did a compression test while I was having the cams welded yesterday and have 150 psi across. 1 cylinder shows 125 psi, and the other was at 110.

 

[ritmusic2k]

Hmm.

My only experience is on the v6, so my info might be invalid...

...but when I compression tested my engine, each cylinder fired up to 110-120psi on the first stroke, and then up to between 220-240psi on the second... maxing out there. Did you only test compression for one stroke's worth, or did you keep cranking it until the gauge maxes out?

 

[wymjym]

I checked mine a few weeks ago. Cold (50 degrees outside). With throttle opened I got 165~172 in 7 and 150 in one. My engine had a group of valves replaced less than 80 miles ago so I'm hoping the low cylinders valves will beat the seat a bit and seal better.
wj

 

[pitbull]

I cranked my car aprox 10 times on each cylinder. After about 4 turns they would max at 150 psi. I also pulled all the plugs at once so no cylinder had plugs in it when I did the test

 

[SHOZ123]

Time to clean the rings with some Auto-RX

 

[pitbull]

I just googled that to find out what it was.. Sounds like good stuff, do you recommend using it, and have you torn apart any engines to see first hand how well it works? I'll have to order it off the website because they don't sell that here in Ontario that I know of.

I am going to try putting the plugs back in and only removing one plug at a time to see if that makes a difference. I was taught to pull them all at once to get a true reading (does it ever sound odd when it cranks over)

 

[SHOZ123]

It's only available on line. I have used it in all my cars. Never torn an engine down afterwards, after all that is what I was trying to avoid. But the oil consumption and blow by was reduced in all the cars I used it on. Some rather dramatically.

 

[cjdavid]

so does it effect, or is it as effective with synthetic oil?

 

[SHOZ123]

It is recommended to use it with dino oil for both the wash and rinse phase.

 

[wood_e]

I used ARX on my Audi and it seems to have helped! Run dino for the clean and rinse cycles...

 

[cjdavid]

It is recommended to use it with dino oil for both the wash and rinse phase.

Thanks. so its no problem to go back to synthetic afterwards then. I shall give it a try after my upcoming road trip.