I suspect broken ring lands but i haven't torn into it yet. ive got the typical smoke screen effect at idle and WOT. It still drives and boosts but smokes like crazy, with a slightly different tone comming from the motor. What kind of confused me at first was i had just installed a Zex cam 2 days ago and was just doing touch up tuning while on the way to school when i felt a very slight jolt of power loss (a/f 12:1-12.3:1) but i didn't think too much of it till i noticed that i was smoking really excesively while crusing. I pulled over at the nearest gas station and noticed that i was leaking oil all over from what looked to be comming from the cam seal. I checked oil and it was really low. i made it home hoping that it was just a cam seal that i had reused...

Compresion tester showed me different...
4 / 3 / 2 / 1
210/120/209/212

looks like #3 is the culprit.

It was bound to happen sometime soon... The set up consisted of z6/SOHC ZC t3/t4 50trim @ 10psi...
its just big inconvienience for me right now b/c i don't have much time to work on my car due to summer school.

well i'll get some pics up ASAP.

p.s. The Zex cam ------- rips... and i noticed quicker spool of about 600-700RPM.

anyone in Eastern Washington have a complete shortblock?

 

Yea man get some pics. How long did you run this set-up? What kind of 1/4 did you pull?


JP

 

ive been running this setup since december. Thats funny that you ask what 1/4 times... i was gonna time it this weekend since i got the zex cam put in.

 

That sucks... right as you were re-tuning for the cam too?

What's the plan? Replace the pistons with some more stockers?

 

I tuned it the day i installed the cam but i usually like to tinker with it for the next couple of days just to make sure everything is perfect... so much for that. Honestly i don't know what happened, total timing is medium and A/F is good. I'm starting to wonder if the hard driving the day before had something to do with it, b/c i was driving it pretty hard during the day when it was hot out.

i'm ripping the z6 head off and putting it on a A6 block for now so just i can get up and running asap.

 

Stock block and all, huh? That's a big turbo, t3/t4? Your clutch was gone that day, huh? LOL.


JP

 

Hmmm I don't know man, 12.3-12.4 seems a little lean to me for 10 psi.. should have tuned for a safe 11.5-11.7ish imo..

I notice after tuning mine, with a 15-20 degree weather change(morning compared to evening), my AFR goes from 11.8 ish in the morning to 12.2 ish or so in the evening...

 

go to guy your dumb. its only a 50 trim. how is his clutch gone? geez your so stupid i cant believe people go to you for answers. 12.3 is a bit lean i would think the 11.5-12 is a safer range whats your timing like at full boost?

 

yeah i didn't really understand any of that either...

I usually use a 12:1 as target A/F but you know how it goes... its gonna deviate a little. your right though i probably should have kept it somewhere in the mid 11s especially with my relatively high comp. setup and summer weather. My totally timming is 19.5* @ 10psi which i consider about medium, and safe.
o
I think it was just the combination of hard driving in the heat, mini me setup, and 10lbs of boost... equated to just enough detonation to pop the ringlands.

 

You change ur cam timing when u put the zex cam in ?