Traction control at the track?

[yyoo]

I see some anxiety here with respect to turning off DSC at the track. So I'm curious as to who uses DSC at the track and why?

One of the great pleasures and benefits of taking a car to the track is to learn car control at speed. Tough to do with DSC on.

Back when I started in HPDE some ten years ago, most instructors recommended turning DSC off. So the only times I've used DSC at the track is on wet days, and even then I sometimes turn it off to practice being smooth.

Has conventional wisdom changed? Is the standard practice to keep traction control on if you're a newbie or even an intermediate driver?

Admittedly, when I started tracking it was in a 220-hp 2001 BMW 330i. The E9x M3 has 200 additional horses. However, if anything, the M3 is easier to control at the limit and, in stock form, has just as much understeer as my old 330i.

[ThunderMoose]

I will probably get ripped apart by the purists. But I think its ok to leave DSC on at first. The one argument is that DSC hides your mistakes, but I think you can still get a sense of how well (or bad your driving) by how much DSC is intervening. I think when you can get around the track consistently with little or no intervention by DSC, then you're ready to leave it off.

[sleepless]

I think plenty of people simply want to enjoy their $70K toy at speed and still feel reasonably confident they'll be driving their kids to school in it the next day.

[yyoo]

Originally Posted by sleepless

I think plenty of people simply want to enjoy their $70K toy at speed and still feel reasonably confident they'll be driving their kids to school in it the next day.

Don't overdrive!

And buy track insurance.

[sleepless]

Originally Posted by yyoo

Don't overdrive!

And buy track insurance.

Isn't that precisely the purpose of DSC?

[yyoo]

Originally Posted by sleepless

Isn't that precisely the purpose of DSC?

Track insurance is a good idea regardless. DSC won't save you from a mechanical or the bad driving of another.

As for overdriving, your brain and right foot are the first line of defense. And if you acquire good car control skills, they are your second line of defense as well.

I can understand how DSC may give someone peace of mind at the track, but sometimes that's a false sense of security. Laws of physics still apply. If you're going too fast, no driving aid will save you. I remember a couple of Audi events in the rain in which multiple AWD cars wrecked. The mechanical aids helped them go faster in the wet, so when the laws of physics did catch up with them, they were going pretty fast into walls.

[sleepless]

Originally Posted by yyoo

Track insurance is a good idea regardless. DSC won't save you from a mechanical or the bad driving of another.

As for overdriving, your brain and right foot are the first line of defense. And if you acquire good car control skills, they are your second line of defense as well.

I can understand how DSC may give someone peace of mind at the track, but sometimes that's a false sense of security. Laws of physics still apply. If you're going too fast, no driving aid will save you. I remember a couple of Audi events in the rain in which multiple AWD cars wrecked. The mechanical aids helped them go faster in the wet, so when the laws of physics did catch up with them, they were going pretty fast into walls.

I totally agree with you on all points when talking about a reasonably skilled driver. But, I think for the average owner that goes out a few times a year which pretty much guarantees they will not acquire adequate skills due to the limited amount of seat time, then they are much better off leaving DSC on.

So, I think the answer is "depends".

[yyoo]

Originally Posted by sleepless

I totally agree with you on all points when talking about a reasonably skilled driver. But, I think for the average owner that goes out a few times a year which pretty much guarantees they will not acquire adequate skills due to the limited amount of seat time, then they are much better off leaving DSC on.

So, I think the answer is "depends".

I think the risks of running without traction control are exaggerated, particularly for beginners who are not going fast and who have instructors sitting next to them. Ironically, it's the intermediate or advanced driver driving solo who might be 'saved' by traction control since they tend to be the folks that wreck. But I wouldn't advocate for advanced or even intermediate drivers keeping traction control on.

[LiM3y]

Originally Posted by sleepless

I totally agree with you on all points when talking about a reasonably skilled driver. But, I think for the average owner that goes out a few times a year which pretty much guarantees they will not acquire adequate skills due to the limited amount of seat time, then they are much better off leaving DSC on.

So, I think the answer is "depends".

You are recommending turning off DSC and wearing adult diapers?

[Gearhead999s]

I always turn mine off 100% when on the track even in the wet.I do not think this should be the norm for everybody who tracks an M3 as you need to have well developed car control in order to do this safely.That should be a mandatory part of any driver training IMO for anybody who wants to enjoy their M3 at the limit regardless of the conditions.
I did an Audi experiance event this past summer and part of it was skid pad with with car control exersizes on wet plastic.The instructors were telling me that when they conduct these exersizes in Northern climates it usually quite boring as most people have it figured out but in the southern states it is usually quite the opposite and can be quite enertaining.When we were kids with a fresh licence the wintertime was the way to experince driving & car control at the limit at slow speeds with very little grip as wrecking your parents car was not a good thing

[CanAutM3]

Originally Posted by LiM3y

You are recommending turning off DSC and wearing adult diapers?

[CanAutM3]

I run DSC fully off in the dry. I find the car does not behave the same way at the limit with DSC or MDM on. I feel the car is smoother and more controlable to subtle inputs with DSC off. Further, since I am running a square set-up, this means that the wheel diameter ratio front to rear is slightly different than stock. So DSC believes that the rear tires are spinning slightly faster than they should and kicks-in more often.

I will however use MDM running the first time on a new track, or in the first laps of the day when the track is still dirty (unknown track conditions). Hey the help is there, might as well use it .

I used to run DSC off in the wet also, until I was served I nice piece of humble pie. I hit a small puddle of water going straight at 110mph, the car snapped sideways so fast, I never saw it coming . I am lucky that I did not total the car or get hurt, but it did cost me quite a few $$ to fix . I am not a newbie (been tracking cars for almost 20 years), but no Senna either, so I now keep the nannies on in the wet.

As for novice students, I agree it "depends" (not the diapers). When they are humble and want to learn, I am OK with them swithing off the aids. It is their car so I leave it up to them. However, some of them come with extremely powerful machines and just want to show off how good they are, then I insist "all aids on", it's my life on the line after all .

[Brainofjjj]

I agree with the above post. I run MDM in for the first session or until I'm warmed up and comfortable. Leaving DSC on is safer for the beginner obviously but you won't learn proper car control since the car is intervening. The M school guys will say to leave it on as well and to notice when it kicks in. This will show when you're overdriving. This is only at the beginner level since you need it off to rotate the car properly.
I leave it on for new tracks as well.

Having DSC or any traction control is new to me since my former track cars are a lotus Elise with none, a base 350z with none and a 240z.

[LiM3y]

I want more skid pan time before going MDM -> "Kommando" (no artificial barriers, i.e. DSC off)

Fortunately my local BMW club is running such an event in April, just in time.

[sleepless]

Originally Posted by yyoo

But I wouldn't advocate for advanced or even intermediate drivers keeping traction control on.

Personally, the only thing I advocate regarding DSC is educating people on the ramifications, then let people decide on what is comfortable for them. We aren't racing, just enjoying the car and the sport.

The biggest practical drawback of DSC is that it overworks the brakes if you get into it a lot. C5 Corvettes are notorious for cracking rear rotors from overheating due to DSC intervention. I've been tracking a 2006 Cayman S for the last 6 years and they too destroy rear brakes.

The other issue is that until recently, most DSC systems are too intrusive. My Comp Package E46 M3 had the less intrusive DSC but it still sucked so drove with it off. I just bought my E90 so have not had a chance to assess it's DSC. The plus side of an intrusive DSC is that you can use its intrusion as a sign of the cars traction, just as you can use tire squeal and other sensory inputs.

DSC is tool, use it if it is useful to you. Okay, that is what I advocate regarding DSC

Except for LiM3y, for whom I recommending turning off DSC and wearing adult diapers

[r53s65e90]

Based on my experiments at these specific tracks (the only ones I have been on anyway) here is what I have observed:

Laguna Seca: MDM is generally not intrusive except at turn 6 and turn 1. In these 2 cases the DSC light comes on even though it does not seem necessary. At these turns with DSC off the car is perfectly happy at the same speed. My guess is that at turn 6 the bump throws MDM off and at turn 1 the speed of 100+ mph and slight drop does the same. At turn 6 MDM kills the power needed to accelerate out of the corner. I haven't done a lap time comparison between the 2 as I drive with DSC off, but MDM does pretty well for what it is. It even allows mild oversteer at the other turns before it kicks in.

Infineon: A similar story here. MDM comes on for no good reason at turn 1 (100+ mph turn) and turn 6 (carousel, high g 70mph turn). With DSC off at the same speeds at the same turns the car is just fine. MDM of course does not allow you to drift around turn 7 (a safe place to do so) but is still allows for mild oversteer to develop.

Thunderhill: MDM incorrectly comes on at turn 8 which is a very high speed turn and stays put otherwise. It never comes on for example at turn 2, which is a very long left hand turn, unless prdovoked.

In all the above cases I described, when driving with DSC off the car is totally happy and MDM comes on incorrectly. So I think the car can still be enjoyed with MDM on, unless you want to oversteer for fun or doing time trials.

Keep in mind that even with DSC off the car is very predictable and never abrupt provided the driver stays concentrated on the road. I have had minor tank slappers occasionally when I found myself thinking about stupid things while driving on track with DSC off.

Of course DSC fully on is way to intrusive. I am reminded of this when I forget to push the M button that has my preferred settings: (Steering: Sport; EDC: Sport; Throttle: Normal; DSC=OFF; S4 or S5 depending on mood).

I hope the can help you choose for yourself.

Experimental setup:
Stock everything M3 with stock 18' tire sizes (RS-3 or RE-11). Advanced group driver.

[wwjd15]

DSC on will kill your driving skill as your experience going up.
It allows you FLOOR the gas at all time at pretty much any situation without spinning out.

I always say keep the DSC on until you feel comfortable with speed.

[SamS]

Originally Posted by r53s65e90

Based on my experiments at these specific tracks (the only ones I have been on anyway) here is what I have observed:

Very nice write up.

My track experience in BMWs is limited to PCD driving an E90M ZCP. Full on DSC was fairly intrusive, MDM was much better. Dumb question: other than "feeling" DSC/MDM interaction to the car, just how are you noticing the red light? I admit I wasn't looking closely when I wasn on the track, and I guess I forget to look when I'm driving on the street. It never blinks on the instrument panel, just the Hazard light triangle, correct?

[MaxL]

To OP's original question - things changed for sure - off at 60MPH is most likely to be stopped by grass/gravel trap. Off at 100MPH is many times more likely to cause a roll or put you into the wall. Higher speeds and heavier cars with the same run offs increase the cost of mistakes, so nannies are more important.

I never use the normal (non-MDM) mode on the track because it's blocks any rotation completely and thus changes driving feel too much. I once had it on thinking I was in MDM and almost had an off because adding throttle to push the car around the bend just did nothing.

But MDM has it's uses, I think - for example, I use it when learning a new track to make sure I have safety net if a turn "surprises" me. I know ideally that should not happen, but sometimes it does on a new track. Another time when I use it is when experimenting with the line or moving braking points - sometimes such experiments may cause "oh-shit" moments, so trying the experimental approach with MDM is a good safety net - important for a really fast car without racing-grade safety equipment. I wish there was a more track-friendly mode, like Corvettes have - something that let's you slide as much as you need and intervenes only during inevitable spin.

[r53s65e90]

Originally Posted by SamS

Very nice write up.

...other than "feeling" DSC/MDM interaction to the car, just how are you noticing the red light? I admit I wasn't looking closely when I wasn on the track, and I guess I forget to look when I'm driving on the street. It never blinks on the instrument panel, just the Hazard light triangle, correct?

I am relying on the hazard triangle to come on. MDM does not blink. Since I was deliberately doing an experiment on tracks I am very comfortable with, I was paying attention to the light. Peripheral vision can pick it up easily.

[Gearhead999s]

Originally Posted by MaxL

To OP's original question - things changed for sure - off at 60MPH is most likely to be stopped by grass/gravel trap. Off at 100MPH is many times more likely to cause a roll or put you into the wall. Higher speeds and heavier cars with the same run offs increase the cost of mistakes, so nannies are more important.

I never use the normal (non-MDM) mode on the track because it's blocks any rotation completely and thus changes driving feel too much. I once had it on thinking I was in MDM and almost had an off because adding throttle to push the car around the bend just did nothing.

But MDM has it's uses, I think - for example, I use it when learning a new track to make sure I have safety net if a turn "surprises" me. I know ideally that should not happen, but sometimes it does on a new track. Another time when I use it is when experimenting with the line or moving braking points - sometimes such experiments may cause "oh-shit" moments, so trying the experimental approach with MDM is a good safety net - important for a really fast car without racing-grade safety equipment. I wish there was a more track-friendly mode, like Corvettes have - something that let's you slide as much as you need and intervenes only during inevitable spin.

The Corvette's "Comp "Mode"is just like our MDM and way too intrusive if you want to work the car on its limit.I used to have a Z06 & a C6 so I have experianced this on those cars.MDM is just about useless with a square setup as it impedes power delivery with the mildest of slip angles.

[SamS]

Originally Posted by r53s65e90

I am relying on the hazard triangle to come on. MDM does not blink. Since I was deliberately doing an experiment on tracks I am very comfortable with, I was paying attention to the light. Peripheral vision can pick it up easily.

Thanks. I will pay closer attention to the hazard triangle. If you're a novice (like me) you might be more concerned with the driving than the blinking