Ranger

At an Atco track rental yesterday, my C6Z on stock tires got very loose on the 1-2 shift. Active Handling kept me from hitting the wall. Fortunately for my safety and wallet, I was running, as always, in Traction System Off, that’s one push of the console button. It keeps the aggressive form of Active Handling available to help the driver maintain control of the car in situations like the one I faced.

After an uneventful, good launch, I made a very fast shift (with full lift of the throttle) to 2d gear at 7000 with both rear tires in the racing groove. Instantly the stock rear tires spun massively and the tach hit the limiter in 2d. The rear-end jigged hard right but aggressive-AH intervened. I lifted immediately. The rear then jigged hard left and AH re-intervened; the car settled down and went straight.

I believe the cause of the incident was water on the racing surface.

Had I been running in Competitive Driving mode with its relaxed AH algorithm, I probably would have hit the wall, ruining the day, week and month and wrecking my wallet too.

So please spread a word of warning to C6Z and C6 owners: if they are planning max acceleration runs on the street or the drag strip, push the console button just once, entering Traction System Off. They want the aggressive form of Active Handling to help deal with unforeseen hazards.

Ranger

SC TROJAN GRAD

Ranger-

what happens if you don't push the button? please explain.

Pio

Ranger, this advice is great for those who can control their cars in case the rear starts slipping sideways.

You have a massive amount of self control and abort a run when something goes wrong. Many people, me included, try to salvage the run and end up in a bad position.

I remember when Ram Air Tony (an old forum mod and still a member) lost his C5Z when he lost control and went into the wall. He swore never to run in anything but competition mode from there on.

I guess what I'm saying is - we've been told for years that in order to keep it "safe" keep it in "competition mode".

95jersey

If you ran at Atco in the recent few days, then it was cold and from my experience anything under about 55F, you can expect to get ZERO traction from a hard launch in a 500hp car. I am not saying water from the water box couldn't of helped caused the issue, but below 55F, drag racing without specific tires is a worthless cause.

Ranger

On start of the engine, the default setting for the Traction Control System is Traction System On and (aggressive) Active Handling On. This will allow a small amount of rear wheel spin without intervention.

One push of the button allows unlimited wheel spin.

Aggressive Active Handling is integral to both those settings.

When max acceleration is intended, the rear tires need freedom to spin lest engine power be constrained. That's one purpose of Traction System Off.

Hi Pio.

In C5s, the desired setting was Competitive Driving mode, as Tony (and many others) found the hard way. In C6s you want "traction System Off.

More than one new C6 owner learned the hard way that Comp mode won't keep you off the wall. That's because its form of Active Handling is relaxed.

Before I made my first passes at the drags in the C6Z I studied the service manual and the owner's manual. I wanted to know the safe setting for max acceleration.

Yesterday, I was happy I'd done that homework.

Ranger

SC TROJAN GRAD

thank you Ranger, I went to track yesterday and I never pushed the button. I was happy to make it down the track with hitting all my shifts. I am working on my launch and shifting. Speed will come with more track time. Your guide with shifting with the thumb "not on the shifter" has helped a lot. I want to drive the car, and not have the car to drive me

Pio

This might be the reason I dont have my C6Z anymore. I wish I knew this before hand - would you agree that its counterintuitive? I always thought "competiton mode" would keep me out of trouble.

As always, thanks for the great info...

PARTSGUY1

So now its starting to make sense. i thought all this time that the active handling was just very lazy on my new Z. The car gets really out of shape now with the temps but i am with others here who thought traction control off is the danger zone. Not that i care other than just knowledge of the vehicle can you turn off active handling on the new z.

Ranger

Pio, I agree that owners making the transition from C5 to C6 need a warning about the change in AH settings. Unfortunately, the C6 AH difference between Traction System Off and Competitive Driving mode is not documented in the owner's manual. But it's been covered in public oral briefings by the Corvette engineering staff.

I've tried to make the importance of running in Traction System Off a part of all my racing technique posts.

PARTSGUY1, as a straight line acceleration practioner/racer, I never use Comp mode in the C6Z. Too risky for me.

Ranger

GARY2004Z06

Ranger,
Great advise. Both you and Ron had a close call yesterday. Even tough you did not eclipse your best run, your runs were great. Being astute, you realized that the water box was out of control and caused numerous problems. Once that was cured, we all enjoyed better runs.
Good to see you again.
Gary

Ranger

My experience at Atco is very limited, just five November track rentals through the years. But on burnout-heated factory-stock Goodyear tires I get pretty consistent good traction down to a track surface temp of 47 degrees. That assumes the surface is free of water and other liquids.

At the time of the incident in question, the track surface temp was 53-54 degrees. Of course I agree that a warmer surface is better. But the sun was not cooperating.

Ranger

yell03

Ranger -

GREAT ADVICE as always.

This will probably save some people from a very costly mistake.

I was blown away the other day when just rolling in to the throttle in 2nd gear my tires broke loose at around 65mph.

These cars are very powerful and if GM wants to give me electronic safety measures I'll take all the help I can get.

Howard

Nanook

Is it just me or does it not seem that the car ALWAYS spins/kicks out to the right?....WHY?

XXXEsq

Ranger,

Thanks again for all you do for this forum. I agree with the previous posts that the naming of the two modes is counter-intuitive. From now on, its TCoff for straight line and Comp for the twisties, but only with plenty of run-off available. My wallet isn't bottomless....

orangecrrrush

Guys,

I have a 07C6Z06 and last feb I lost control of the car with the AH off. I now drive in comp mode.

Unlike my C5, the C6 is very unstable at hard launches. My c5 squats, where my c6 doesn't.

With comp mode i can feel the *** end trying to break lose... kinda scary.

HamsHall

a lot to know

Exterminator

Thanks for posting Ranger

O7zeeO6

Its good to hear that you and your car are ok Ranger. Same thing happened on my last run last Sunday once I shifted to 2nd.

I was reading up on the Competitive mode feature in an effort to fully understand what it is and what it does, but after reading what you wrote, I am as confused before I started reading it. I'm not sure if its different from an 06, but my understanding after reading the manual is that the competitive mode gives the driver full control of the rear wheels (meaning allows wheel spin) while having Active Handling feature on. How is this different from pushing the button only once (traction control off)? You are right, the manual doesn't discuss the difference between the competitive mode and "traction control off" positions. It also seems that the "traction control off" is a more risky setting to be driving in since a warning light comes on when it is turned off, but the competitive driving mode doesn't have a warning light. Did GM fully screwed up on writing their manual or what? Does the 08 manual has more/better explanation on the difference between the two settings? If you have an 08, please chime in.

I pasted the page that talks about competitive driving mode below

'06 Quicksilver Z06

Great advice.

I have had the rear end break loose on mine on the 1-2 shift now at least twice. The first time it was in competitive mode an dI nearly lost control of the car. The second time was with one push of the button to Traction Control Off.

Both times may very well have been due to water on the surface of the track. At my home track, they routinely spray down water, and plenty of it, for burnouts and you cannot drive around it.

This leaves water on the front tires and on 2500-3000 mile runflats, water in the tread grooves with anything less than a longer slower burnout. Something most people are reluctant to do on street tires.

Dr.Ron

Same thing happened to me as Ranger yesterday (Monday) at Atco, on the 1-2 shift, as Gary mentioned above. I too lifted and got the AH active DIC message.

It is smart to leave it on as a safety measure!!

Ron