My last effort

[LantanaTX]

Typically, if valve seals are bad you get a lot of smoke at start up after sitting a while, like overnight. After start up, smoke decreases. Bad rings will show smoke increase as you get on it. If compression is good and you aren't getting a ton of smoke at start up which clears up somewhat after warning up, I would be looking at the crankcase ventilation, maybe even adding a catch can if that is possible on these engines. Adding a catch can will keep oil from entering the intake and then if you are still blowing smoke you know it is a more serious engine issue.

[Hog]

maybe it needs an Italian tune up? Sitting around and being idled in the cold all Winter isnt helping. I would go burn off all that Winter buildup abd get the engine hot an see how it behaves then.
It would be nice to watch the tailpipes during a WOT acceleration pass from an other car. following the Z.

Leakdown test could be beneficial. Proper compression tester technique will determine if rings or valves are an issue. Dry 1st, then wet.

[Dynomite]

Originally Posted by Mitsumark

PCV system is operating effectively as Plenty of suction is present at the valves, and on both Plenum PCV pipes..Removing the oil cap when running there is no blowby coming out.

I see in another thread you recently replaced the PCV Valves (CV913C & CV769C)....so this may be a non issue

What is the history of this oil burning issue??
Sounds like this oil burning issue did not progress over a driving period of say 50K miles but over a driving period of a few hundred miles or less and if that is the case.....you can eliminate all sorts of potential mechanical issues.

Plenty of suction present at the PCV valves is not an indication of a properly working PCV system

POSITIVE CRANKCASE VENTILATION
PCV System TIPS
PCV valves sources TIPS
MAP Hose TIPS
PCV connector & MAP sensor
PCV system
PCV source
Crankcase Ventilation
PCV and Cam Cover Vents
Difference between 90' and 91' heads
Cam cover vent material
Cam cover SS vent material

[Racinfan83]

I have no technical answers for you here - but I do know that Marc Haibeck works late in the evenings. As in like into the night. I would suggest maybe e-mailing the link to the thread/threads to him - and then giving him a call later in the evening. zr1specialist.com

[GOLDCYLON]

After rereading through all this suggest checking your injector housing gaskets. I think you may find a crack in the gasket or perhaps they are not tight. Either way thats my final "Easy" thought on oil consumption. GC

[Mitsumark]

Re: My last effort
maybe it needs an Italian tune up? Sitting around and being idled in the cold all Winter isnt helping. I would go burn off all that Winter buildup abd get the engine hot an see how it behaves then.
It would be nice to watch the tailpipes during a WOT acceleration pass from an other car. following the Z.

Believe me..It's had frequent Italian tuneups..When I said a lot of idling it didn't mean just to start it and let it run..I was daily driving this car on all dry days..Just have a phobia about warming up my cars thourally in extremely cold temps like we've had here in NJ..

Dyno- I went through every one of those threads that you posted from the archives..I'm positive my PCV hooked up correctly and functioning as it should.I triple checked every aspect of it..I Even replaced 2 new sets of PCV valves twice within 200 miles just to be sure I didn't get a defect..Now,,I was aware that the exhaust smoke could be coming from the cam cover filters being missing or damaged, and also the valve seals..What I did not know before reading your archives,and just mentioned by Gold that it could be coming from a the IH gaskets..I just had the plenum off this week to remove the secondaries..Although I didn't remove the IHs I was expecting to see some oil present in the valley..Not a trace around the Breather box or the bases of the IHs..She was oil free except maybe a teaspoon in the plenum..So I guess it's possible the IH gaskets could be leaking internally and not externally?The car is smoking as show in the videos without any load..Smoke increases with throttle..The smoke only comes when fully warmed up..No smoke cold for the first 15 min..

[LantanaTX]

If no smoke on start up for the first 15 minutes, I highly doubt it is bad seals.

[Pete]

You don't have to remove cam covers to replace the sponge in them just to see if it stops smoking, just put a in line filter
First check the cam cover lines for oil some is ok if they are loaded dripping then put a in line filter.

Pete

[Mitsumark]

Ahh..Pete the man..Heard alot about you..On my way home to from work now to do what you suggested with the cam filter tubes.Also gonna try a 20/50 oil change..Man how I wish you were local..Im fighting with myself on driving this thing out to you or Marc and taking a Greyhound home..You do full rebuilds?If so PM me your number..Id like to discuss my options if I cant figure it out,and if its worth fixing if I cant..

[FU]

Mark.....I'm out of Long Island and have made the trip often. The Cheecago gentlemen take care of you. Mine's out there right now getting a tweek done here and there. Either way it's cheaper to fly. Shipping is 600 from LI. Should be cheaper from NJ. I should be flying there within the next month give or take, and driving back. Can I be of any help ? Where in NJ are you ?