Q: “I’m a novice with a couple HPDE track events and I’m hooked. I’m getting conflicting information as to whether I should turn Traction Control off or leave it on while learning to drive faster. I drive a 2017 Mazda Miata so power isn’t huge. I know that TC may save me from myself, but might it also mask some of the ‘limit sensors’?”
A: Ahhh, the most-asked question of them all! And one that is impossible to answer definitively. And everyone has their own opinion. So, here’s mine… It depends! 🙂
In the perfect world all drivers would start track driving in low-horsepower, low-grip cars with no traction control (E30 BMWs, early Miatas), and the driver would learn car control at relatively low risk. But so many cars have TC now, so it’s less likely that a driver will not have it as an option. So, what to do? I believe a driver should start track driving with TC on, and then when he/she can tell when the system is helping, then and only then should the driver turn it off. If the driver can’t tell whether it’s assisting or not, then the driver has not learned enough about sensing what the car is doing. Once the driver has developed the ability to sense when TC is helping, then it’s a good idea to turn it off so he/she can fine-tune their car control skills.
Yes, TC masks limit sensors. They also cover up mistakes that drivers make – often mistakes that the driver doesn’t even realize they’re making. TC also reduces the chances of crashing. So, some good things, some less-than-good.
Since I don’t know what level you’re at with your ability to sense the limits of your car, I can’t say for sure what you should do. But based on you saying you’re a novice with a couple of events under your belt, I’d suggest leaving TC on until you can consistently tell exactly when it’s assisting – when it’s activating. Once you know exactly when it’s activating, and even when you’re able to predict when it’s going to kick in, then consider turning it off.
I’m not sure what the new Miata has in terms of settings for TC – does it have steps? If so, turn it one step off, where it activates a little, but not fully; then with more experience, turn it off entirely. I also don’t know whether your car has stability control in addition to TC? If so, I’d emphasize what I said about TC.
I’ve only got about 20 track days under my belt; I was pretty impressed though when after being asked this question an instructor once offered to drive my car for a lap. He ran significantly faster than I did, as expected, but told me to watch the dash carefully – no TC at any point (this was in the “sport” setting, about 70% off). He suggested that I use it as a tool to work on smoothness.
There have been some times that have consistently lit it up though, such as an uphill hairpin left or turns 4-5-6 at COTA, where I’ve found that disabling it completely lets me run much more smoothly, if nervously.
Once you have full understanding of what it does and when/why it activates, its very good to turn it off, only if you have the skill to manually correct in a situation. I took some time to confidently turn it off before going onto track. But sometimes I forget, and get a little surprised when it activates. I have measured (with my driving style) that TC is around 2 seconds slower on a 2.5km track with 8 turns. One place in particular is a long fast bend where the TC activates due to slight lateral drift. Cuts out the throttle in fast, short bursts which slows you down.
Regarding the specifics of the technology itself, look at ABS, TC, ESC (aka ESP, Stabilitrac, DSTC, and other mfg trademarks) as a pyramid of computer controlled sensor and actuator driver assistance systems.
The foundation is ABS. Wheel speed sensors monitor tire rotation and intervene via hydraulic servo pulsing fluid pressure to maintain tire rotation under braking.
Layer on Traction Control, which uses the same wheel sensors but this time during throttle-on, to maintain grip during acceleration (uses brake to slow individual wheels and may also reduce engine output).
At the peak of the pyramid is ESC (Electronic Stability Control). Using the above mentioned sensors, brake and engine actuators, ESC adds a yaw sensor (rate of rotation about a vertical axis), 3-axis accelerometer, and steering wheel position sensor. ESC compares intended path (steering position) vs actual path (yaw, lateral acceleration, speed) during cornering.
ESC utilizes individual brake intervention to attempt to maintain intended path.
Front tire skid (understeer) is reduced via inside rear brake actuation. Rear tire skid (oversteer) is reduced via outside front brake actuation.
On-track use of ESC can lead to excessive brake usage. I’ve seen brake pads wiped out in 20 minutes, especially rear brakes due to understeer.
Thanks for sharing the info, Rob. It’s almost funny how rear brake pads wear out faster now, right? Well, not that funny…
I have been turning TC off since I’ve been driving a track car that has it for about 4 years now. Before that none of my track cars had TC. Sometimes I forget to turn it off. On one particular occasion I triggered TC in what I thought was a benign location. I decided to leave it on and do a few more laps to correct my “mistake” in that “corner” (easy turn-in while cresting a hill) trying to avoid triggering TC. The result is that I gained a few tenths just by being smoother with my steering input. Without TC I would not have been aware I could gain time in that location. My point is that even if you normally drive without TC, turning it back on can be effective for correcting mistakes in some corners. The idea is to prevent TC from triggering while still turning a fast lap.
That’s a great point, and I agree with you 100%.