ok....i have read the manual and i am trying to understand how these systems work.....traction control keeps rear wheels from spinning to much.......launch control also keeps wheels from spinning to much for fast starts....active handling applies the brakes when needed?when does active handling "engage"?for all out performance do you want to be in "competive mode"?i have 2011 g.s....with stick but not magnetic ride option...........thanks,j.k.

 

Active handling engages individual brakes to try to keep the car in the direction you want it to go. It engages when the car senses it is going in a different direction than intended (spinning/fishtailing, etc).

What you want depends upon what you mean by "all out performance". On a drag strip? Road course? Street? Competitive mode allows more driver control and less intervention. A really good/experienced track driver will be faster (on a track) with it off. So for max performance (on a track) you want it off or in competitive mode, depending upon driving skills. On a drag strip, you want traction control off. Launch control will be more consistent, but again, a good driver can out-drive it.

In my own personal opinion, I would not turn active handling completely off on the street. If it is engaging (particularly in competitive mode) on the street you are close enough to the limits, that it's a good idea to have on - particularly due to the unpredictable road conditions general street driving presents, but plenty of people disagree

 

thanks for reply z28...so active handling kicks in on all four wheels by applying brakes if you screwed up?and traction control just controls rear wheels if they are spinning?thanks,j.k.

 

Just about right. Good thing about active handling is it can work on all 4 wheels, but has the ability to work only one wheel at a time if we screw up - as you appropriately put it. It has abilities the driver doesn't, which is to control individual brakes to straighten the car.

 

 

Essentially there are 4 different settings for TC/AH:

1. Every time you start the car - TC and AH are both on
   
2. One push of the button - TC off
   
3. Two pushes of the button within 5 seconds - TC off, AH Comp Mode (AH still on, but lets you slide the rear around a little more before it activates)
   
4. Push and hold button more than 5 seconds (or whatever it takes to get the DIC message) - TC off, and AH completely off

I run track events in Comp, but see no reason to ever turn anything off on the street.

Even on the track with AH full on, if you drive smoothly you will rarely see any intervention from AH.

Bob

 

Bezo6.thanks....i got it.........in compettion mode active handling still active...to a lesser degree......

 

what would be the reason to turn active handling off?

 

First, you need a little more information on what active handling does. As a poster above mentioned it helps you make the car go where you want it to go. It uses inputs from the steering wheel sensor to determine where you are telling the car to go. It then uses inputs from the lateral G and yaw sensors to see how the car is responding to your input. If it is responding too slowly (understeer, push or in NASCAR parlance "tight") the Electronic Brake Control Module (EBCM) applies a single brake at the inside rear wheel (if turning left the inside is the left rear wheel) which yaws the car to the left. If the car is responding too quickly (oversteer or in NASCAR parlance "loose") it will apply a single brake to the outside front wheel (in a left turn the outside front wheel is the right front) which reduces how fast the car is turning (yaw rate) and keeps the back end of the car from coming around.

There are very good reasons for not turning it off. C5s and C6s have more pronounced trailing throttle oversteer than previous Vettes due to being closer to a 50/50 weight distribution. This can catch inexperienced drivers (the vast majority of drivers are inexperienced) when making a turn and they lift their foot from the throttle at the wrong time and the car starts to yaw quicker. They also have enough power to induce power oversteer at almost any time in a corner which catches the dufuses when they think they are being smart but all they are doing is proving to all observers how dimwitted they really are.

When a very good driver is on a road course they may be able to get better lap times by allowing the car to rotate more (oversteer) in a corner than the active handling programming is set up for. That is when the driver turns it off. Most drivers are not that good since it takes a certain amount of skill to balance the oversteer on the edge of disaster with steering and throttle corrections. What AH can do at certain times is allow the driver to hammer the throttle coming out of a turn and keep the rear wheels behind the front by alternately applying the front brakes. With my C5Z I used this feature in an autocross to drive hard off a particularly sharp corner without spinning the car. Just braked as hard as hell using the ABS to max, turned the car around the pylon and as I exited went to full throttle. Rear tires were spinning (TC was turned off) and as I was using the steering wheel to point the car where I wanted to go the front brakes were hammering back and forth to keep the car straight. Everybody kept asking how I was coming off that corner so hard without spinning the car. One of the things that helped me get Fastest Time of the Day.

AH has one big advantage over a human being. It can apply just one brake at the right time. A human doesn't have the individual control interfaces to do that with just the steering wheel, brake and gas pedals. So there are times when it can provide an advantage if you know how it works and practice using it. Just another tool in the tool box.

Bill

 

thank you very much bill..........now i really understand, i just wanted to know how this stuff works............now i do.j.k.

 

If you were drifting, you would need to have it off.

 

Drifting or donuts. (if you can afford the tires)

 

bump

 

"...for all out performance do you want to be in "competive mode"?

I don't know much about launch control so I'll ignore that. Generally speaking, whenever going WOT always shutoff TC. I can seemingly 'over-power' TC at-will but I don't want the system fighting my efforts to accelerate. Feather the throttle if need be. IMO for "all out" performance shutoff all nannies. Comp mode is a great learning tool on a road course, however, it gets to a point where comp mode slows you down. Comp mode shuts-off TC and reduces the level of AH intervention. If I use comp mode on a road course it engages at virtually every corner and curve. When I put the power down coming out of a corner/curve AH kills your throttle response...it just 'flattens' you out. You either have to wait until the car is going straight or go off your line purposely to straighten the car out to regain full acceleration.

I suggest anyone learning to run road courses use comp mode and use it for a good long while....there will be many instances when comp mode will help (maybe even save your butt). In time, after a lot of consistent practice, you'll know when comp mode is actually slowing your lap times. At that point shutoff all nannies and take it down a notch. You'll soon see to what extent AH had been affecting the car. Slow it down and at a measured pace ramp-up your speed and aggression. It's kind of a whole new learning experience without the nannies.

 

Wayne has a 2005, and there could well be differences between model years in exactly how/when the AH intervenes, because my 2006 Z06 virtually never activates the AH when I run road courses in Comp mode.

I attended Spring Mountain a couple years ago when they had '09/'10 cars, and running with AH full on I never had problems with AH intervention - of course their cars are on street rubber, and I certainly wasn't running 10/10ths!!

But, Wayne's car is a pretty well track only car, and he probably drives it a lot harder than I do. I drive to events and run on street tires these days.

I don't do any racing, just HPDE track days, so I'm not looking for podium finishes for better sponsorships or a better ride in a better series - I just want to have fast but safe fun at the track. So I run in Comp.

The only time I have had a serious problem with AH activating in an extremely obnoxious way (basically making the car unsafe to drive on the track with other cars around) was when I had a tire pressure sensor problem - and in that case I couldn't go into Comp mode anyway.

Even when I used to run on R-compound tires in Comp mode I can't ever remember getting any interference from AH at all when running a number of different tracks, except in one case.

When running around the banking at Daytona in Comp mode I used to see the DIC flashing "Active Handling" occassionally - just a brief blinking a couple times around each end of the tri-oval. That was on the old bumpy track surface before it was repaved in 2010.

I didn't feel any jerking from brakes activating or any reduction in power - just saw a couple blinks in the DIC, and only on some laps. I didn't feel any excessive tail wag and I could have turned AH off completely, but if the AH was sensing something I wasn't feeling and it was helping keep me off the wall at 160-165 mph, then I was just going to let it do its thing!!!

They didn't have any HPDE's at Daytona in the fall of 2010 due to requiring the new pavement to "cure" after the repaving. But, in the fall of 2011 I went to a couple of events on the new very smooth track surface. I don't recall seeing any blinks in the DIC while going around the banking, however every couple laps I could feel a definite lack of throttle response and the DIC message in only one place - coming out of NASCAR Turn 4. It only would last about 1/2 second, and again I didn't feel like I needed to turn AH off completely just to avoid that one little activation that may have really been saving my butt!!

I tried several different lines coming out of NASCAR Turn 4, and some lines didn't activate the AH, some did. There's a tunnel under the track there and you used to get a nice little bump right at the turn exit over the tunnel. It doesn't seem to be as pronounced of a bump after the repaving, but there is a definite transition from the steep banking to the front stretch, and the AH must have been sensing something that it felt like it needed to help me out with, and at 160+ and accelerating hard I am happy to accept its help!!

I never get any AH activation at all when throwing the car around quite hard in the infield at Daytona.

Anyway, I agree totally with what Wayne said about using Comp mode until you are VERY familiar with capabilities of a C6 to exceed the limits of your contact patch just about any time you stomp down on the accelerator!!

At Spring Mountain they do a number of different exercises with the AH off on their wet skid pad so you can throw the car around and feel the total loss of traction. You can really only drive the car to its limits when you know where to edge of the cliff is. To find out where that is you need to do something like the Spring Mountain skid pad training, or you need to run hard on the track with AH off and get a feel for when you start to "drift". You'll do some spins and have some offs, so make sure you're only running real hard in corners where there is plenty of runoff when you're trying to learn the limits!!

Just MHO, YMMV!!

Bob

 

great info.thanks

 

Thanks to all that posted info in this thread.