Coming home today I ran into a "wana beat a corvette" guy. This guy literally prevented me from getting over to my exit. I couldn't slow down to get behind him because of traffic behind me and him. Only option was to get in front, every time I sped up ..he did too!. I'm sure this has happened to all of us at one point. Anyways i got a little mad, I down shifted into third and punched it...all I can say is WOW!!!! Now mind you, I have played with my Z, but this was different. I wanted to make this guy eat my dust..you know. The car jumped like a jet ( I recently put on LG headers,street series and got a tune from ECS) and took off. I went into 4 and I was gone. The exit came up quick..real quick. I took it, threw it back into 3 tapped the brake, then into 2. All was well But then I noticed..A lot of smoke coming from ME! When I accelerated to merge- some more came out but quickly disappeared. Of course i pulled over, opened up the hood and checked. Everything was ok. I then went to my tailpipes and yessir..there was the tell tale sign of the "black" on my chrome tips (Corsa pace). Now can anyone help explain this. I'm at at a loss. I don't really burn oil (01 Z) but I do notice more of a "oily smell" since I run my pipes straight (no cats) and I think that is normal. Thanks for any input on this. I'm a little nervous and sorry for the long post.
Don
dcd58

 

Under WOT conditions and anything over 4K you can burn some oil. Not to mention the car running rich when at WOT which is also normal, but you shouldnt see black smoke pour out. Sounds like the tune, and it might be too rich when your wide open.

 

You don't say what color smoke? Bluish for oil , black for fuel rich, white for coolant.

Under wide open, high rpm condition (like Blown 346 mentions) the LSx engine's rings will flutter and allow more oil to bye pass into the combustion chamber. So that when you decelerate the oil built up in the chmaber , manifold, exhaust ect is ejected out thru the tail pipe.

 

Sorry guys.. ok, the smoke was bluish as I stopped, on the tailpipes there was black carbon. I recently had a tune (Late Feb, early March..can't remember off hand) by ECS. Should I be concerned about running a little rich? They must of tuned it this way for a reason.?

Edit: Would a "oil catch can" help this situation?

 

Bluish smoke usually means you are burning a little coolant and that the cololant can be in the oil. I would check that. But, it is normla for your car to run rich, but not to the point of you seeing a cloud of it. The tune is meant to run rich higher in the RPM's to make sure you dont run lean. It sounds like you may be running to rich.

Look at your dyno sheet, what is the A/F ratio at along the dyno run from start to finish?

The exhaust of a efficiently operating engine has little or no color. A dark, smoky exhaust indicates incomplete combustion; the darker the color, the greater the amount of unburned fuel in the exhaust. Incomplete combustion may be due to a number of troubles. Some manufacturers associate a particular type of trouble with the color of the exhaust. The more serious troubles are generally identified with either black or bluish-white exhaust colors.

 

Blue smoke in the conditions you've described are usually indicative of oil burning past the piston rings, not really all that unusual in high performance engines, with a few miles on them. As long as you're not burning a lot of oil, I wouldn't worry about it.

 

[/URL]Edit: Would a "oil catch can" help this situation?[/QUOTE]

Being that oil is getting past your rings, valve guides that would indicate that your using oil to some degree , just as we all are with LSx engines. I see a catch can as a must to keep oil from building into carbon deposits in your cylinders, on the valves, rings. Also oil reduces power by mixing with the fuel/air ratio. CAT converters and O2 sensors fail prematurely due to oil bye pass.

Check the archive on the subject of oil consumption , oil catch cans, '01 ZO6 and you'll find that a $100 or so is well spent. B elow is something to get you started, Read Dave68 conceptualpolymer first to grasp the theory.

http://www.conceptualpolymer.com/corvette_c5_corner.htm

 

You could have an 01 weak ring oil burner like some of us.
Usually its valve guides / seals if you see blue smoke on decel.
Piston rings if you see smoke on acceleration.

But in this case, maybe you just dont beat on your car often and had some oil buildup in the intake that got "blown out" when you got on it.

 

But in this case, maybe you just dont beat on your car often and had some oil buildup in the intake that got "blown out" when you got on it.[/QUOTE]

 

[/QUOTE]
Thanks everyone for the input! You might have something here. I really don't "beat" my car. Sure I hit the gas, but that day was an unusal
day. I will take the car out for a "spin" once the weather dries up some and do the same thing as that day and see what happens. I am also looking into an Oil catch can!
Don
dcd58

 

Blue smoke is indeed oil. If you saw it after deceleration and then when you stepped on it, it could have pulled a little oil down around the valve guides under high engine vacuum and then burned it off when you got on the throttle. I would not worry about it unless it becomes a constant occurrence.

 

 

I agree.

Bill

 

An Update..
Ok, it dried up enough yesterday to take the Z for a spin. I took it to a road that is worthy of the Zees high speed . I did the exact same procedure that caused the smoke to occur the first time. NO smoke this time around,only sweet music from the pipes and amazing back breaking torque . I did it even a little harder this time around. I tell ya, these cars are scary What really is amazing is how fast you can stop if you use the gears. I'm not going to mention how fast I was going, but I'm sure you can imagine. I was by myself and no cars were around me. The road was a little more than 1/2 mile straight, so there was no problems in doing this experiment. I did it 3x and no smoke came out while downshifting to a stop like last time. I also want to mention that before I did this I bought a new PVC valve. Whether this had anything to do with it, I don't know. My car never really burned oil before so I was concerned. I want to thank everyone for their feedback This is just another reason why this forum rocks all others!
dcd58

 

Its not unusually when running with no CATS.

 

I've been told this too..thanks.

 

I have heard some of the early 01 Z06 cars had a problem with rings not seating properly do to being to hard. When GM checked into this they had a service bulletin sent out to dealers to do a repair.




Smokin Aces

 

Going to check up on this..thanks