tbrenny33

Totally agree! It's very odd at first to keep your foot all the way down and in it, specially with just the slightest slip. But like you said once you do it a few times its and get used to it, you realize how good it actually can be.

Bigdog9586

Doesn't the auto need to be in manual mode, first gear too.

AllFlash

The easiest way to do it is to remain in drive but it can be done in manual with the paddles.

tbrenny33

Yup. The one thing I have noticed though, is if you do it in manual mode and you time your shift you can get it to shift right at or just into redline as opposed to it shifting just short

CONMAX

Yes, the A8 has launch control. It may be ok for the street, but it will slow you down at the strip unless you are not very good at the start. My best 60' time W/O launch control is 0.14 quicker than with it on. The 0.14 is a bunch with 60' times between 1.65-1.95s.

Bill Dearborn

Does it really make a difference? Launch control may be a shade slower but is more consistent. The .14 delay can be compensated for in your dial in. The only time the delay would be an issue is in a heads up run with no dial in. There aren't many of those in drag racing any more.

Bill

jmc9981

I been trying to find this answer and haven't had any luck. With the automatic when you do launch control can you actually just mash the pedal and the car will automatically control wheel spin and all that as it shifts through the other gears?

I know that on the manual the second you lift off from the gas to shift that launch control is no longer active. Just wondering if its different with the auto. I don't want to assume that i can mash the pedal and then when it shifts gears have the car break loose and have it go sideways.

tbrenny33

The auto is the same. Enter LC, smash gas and it'll modulate wheel spin, and keep your foot on the gas. I've used it several times on the street and you never need to lift the gas.

azcanuk

Haven't used it in the Z yet but have in a ZR1... which the first time I did it launched so quickly it threw me back into the seat and I lifted the gas ever so slightly, no more LC. Second time, mashed the pedal and kept it mashed, launched like I was coming out of a sling shot..

getburnt

This may be a dumb question but how do you get into LC mode and get the car staged at the strip. It sounds like once it is selected you need to be on the brake and gas pretty fast.

jaden61

Follow directions for your transmission type.

rrm

I have tried all these and the fastest time to 60 is 3.8...really disappointing...rrm

jmc9981

I appreciate the instructions but at the same time it raises more questions lol. I tested launch control once but i could have sworn i did it in automatic mode without the paddle shifters. I know there probably aren't too many automatics so out there so its hard to get a straight answer.
I became very curious after i saw that video of the red corvette crash in to a tree because the driver didnt know that once he shifted in to 2nd gear that he had to feather the throttle because launch control will no longer help you.

So i was wondering since i have an automatic that if i use launch mode and pedal to the metal the entire time as the car shifts through the gears for me, if i'll have the protection from launch control that the computer prevents the tires from breaking loose after first gear. If thats the case that would make the Z06 take off like a rocket in a straight line even for a rookie driver without the worry of going sideways.

VetterFlyer

I liked this from another thread. I like the GM's engineers explanation.

Understand PTM Modes and When to Use Them
Alex Macdonald, lead Corvette development engineer and expert in chassis controls, describes below how they are designed and how he utilizes them


Click the image to open in full size.


Glossary:

TCS - Traction Control System
ESC - Electronic Stability Control
PTM - Performance Traction Management
MR - Magnetic Ride
ELSD - Electronic Limited Slip Differential
ABS - Anti Lock Braking System

Mode uses:
WET: This mode is intended for any driver who is on a wet track. The track should be wet enough to be glossy, not just damp. A damp or drying track will require the driver to decide between WET and DRY modes to get the best performance. Standing water is not recommended as hydroplaning is possible and no TCS system can accurately control a tire that is hydroplaning.

The slip targets are very low, lower than in standard TCS. The MR is in tour mode to maximize mechanical grip since the lower cornering forces don’t require the extra control offered in Sport or Track. ESC is on and uses the normal calibration, not the competitive calibration.

DRY: This mode is for a novice driver on any track or an experienced driver learning a brand new track. I also use it to warm up the tires or run the mold release off of new tires, especially if it’s cold out.

Slip targets here are very similar to normal TCS but will feel very different due to the entry prediction. MR is in Sport to compliment the usage we expect in this mode. ESC is on but uses the competitive calibration.

SPORT 1: This mode is for any driver who is ready to run very competitive lap times while still having stability control on in the background. I use this mode whenever I have a passenger, possible distractions such as data collection, or as I am continuing to become more familiar with a new track.

Slip targets are higher here than in normal TCS. MR is in track mode and ESC is on using the competitive calibration.

SPORT 2: This mode uses the exact same traction control settings as SPORT 1 but turns off ESC completely. This mode is designed as a way to turn off ESC while maintaining a fairly stable TCS calibration. I use it very often. Basically any time where tenths of a second are not critical to my testing or when the tires are getting too hot or wearing out. After 10 to 15 consecutive laps it is likely that your fastest times will be achieved in SPORT 2 rather than RACE.

Slip targets here are the same as SPORT 1. MR is still in track mode and ESC is turned OFF.

RACE: This one is pretty self-explanatory, it’s as fast as we know how to make the car go. This mode is for a well prepared car on relatively new tires with an advanced driver that is completely familiar with the track. The track should be somewhat warm and the tires should be up to temperature.

Slip targets are 100% optimized for forward acceleration, any small variances in the track or tires can result in momentary overslip that will have to be managed by the driver.

A few notes about RACE mode: I approach this mode as a tool to go faster meaning that I think specifically about it when I go to WOT and I try to change or optimize my throttle application point and steering to help the computer do its job. It can do the job better than me but only if I give it good information. A specific example is how I unwind the steering wheel mid corner and as the corner opens up. When learning to drive on track it is good practice to automatically unwind the steering wheel as you apply throttle regardless of the vehicle response (a string tied from throttle toe to steering wheel is the analogy used by some instructors). The problem in RACE PTM is that by doing that you are telling the car you are ready to go straight. It will add power and drive you to a wider line. The best results are found by holding the wheel as steady as you can and pointing the car to corner exit only when it’s time. Obviously you have to be ready to correct for overslip but as you gain trust you will find this is required less often than it feels at first. It is very useful to practice using PTM in the lower modes where you can focus on letting the car go where you point it and not correcting your steering too early.

We find that the calibration settings that achieve the fastest lap times often result in expert drivers feeling like they are being held back slightly on corner exit. Most of the time that extra little bit of slip that an expert driver wants is over the traction peak of the tire and may feel good but is wasting forward acceleration. The restrictive feeling is not there as a safety net, rather, it’s as close as we can operate to the peak capability of the tire in a robust way.

Other notes: The eLSD “PTM mode” is only a slight alteration of its normal track mode. This alteration is required since it is likely to see engine torque values that would not occur without PTM. However, the philosophy of what it’s trying to do and how it’s controlling vehicle dynamics does not change between PTM and TCS/ESC OFF mode.

As for the nannies, that term is a big gray area. I would personally call TCS, PTM, ESC and active rev match nannies but would not call the eLSD or MR dampers nannies. ABS is very gray. ABS, TCS, PTM, ESC and active rev match are trying to do a better job of something you normally do as a driver, steering, throttle, brake or shifting. However, no driver ever controls a differential directly or a shock absorber directly. They are part of the base chassis tuning and can be thought of as a calibration component like a spring or anti roll bar.
ABS is more of a gray area but it is not allowed to be shut off because the capability of the vehicle is so limited without it. You may need 200 bar of brake pressure to get max decel from a wheel that’s on the outside of a corner but the inside wheel would be totally locked at 50 bar. Unless you want a lot of flat spotted tires you need ABS in that situation. Also, somewhat like eLSD and MR, individual wheel brake pressure is something even the best driver can’t physically control without the electronics.

That’s a long way of saying you can shut off TCS, PTM, ESC and active rev match but you can’t shut off MR, eLSD or ABS

VetterFlyer

The image left out of the above message;

http://cimg7.ibsrv.net/gimg/www.corv...06036b8bc7.png

davepl

I've asked before an no one knew, maybe now... what the heck is the difference in the bottom right corner, the "Drag Strip" launch mode? I wonder if its just more aggressive, or what the difference is?

jmc9981

As far as my question and the other member who asked about the drag strip feature i don't see why Chevy didn't feel like they should be providing a detailed clear explanation of these features. A mistake of misinterpreting this information could turn in to a very expensive accident.

jaden61

When I do launch control with my A8 I am in Sport1 mode. You will still have active handling, not sure about traction control after 1st gear, but mine has never chirped into 2nd and the bogged exhaust note is gone in 2nd, so I assume it is not interfering.
Also, the Red Corvette in the trees has had many stories behind it. And at Corvette school they suggest it was his driving style that brought him to that situation. As the "yanker" I think they call it. When he shift he yank the steering wheel too. They teach you the proper technique for shifting also.

jaden61

Mine is from the owner manual.

Mopar Jimmy

At my favorite Sunday test and tune location in Mexico I played around with the launch control for the first time since buying my 16 Z A8 and it worked great and was a great way to get out of the hole with no wheel spin. I first tried it first in sport 1 then sport 2 with no active handling on and it worked great either way and did not get squirelly on the 1/2 shift and on crappy cement totally unprepped surface!

Conmax (and anybody else), did you ever run in the 10s bone stock using launch control with A8 tranny?

Also, what are your best time et and trap running without launch control and launch control?

Thanks gents this place is the best!