Braking....What is/should be taught?

[dcarusillo]

I recently had another discussion w a valued Member about learning how to brake, on track.

It is interesting how the concept of trailing the brakes continues to upset some Drivers....and their cars.

Years ago, SDR was adamant about not even speaking to newer Drivers about trail braking. Not sure what qualifies as a standard teaching recommendation in SDR now, but I wish trail braking was mentioned back then. Even if only brought up as an option. At least there was a shuffle steering vs fixed hand debate.....

Anyway, I came across this blog that really sums up what was previously missed in SDR.

https://racers360.com/education/the-off ... ing-guide/

[kleggo]

Trail braining is an important part of performance driving / tracking.
I never understood why we would only teach that "braking must only be done in a straight line".
Well I guess I do understand.........., but we should also at a minimum discuss trail braking as an option / next step early in the development process.
I suspect most people have an innate understanding of the "friction circle".
They definitely do if they ride bicycles!

[EricMarc-Aurele]

I think it should be taught as a part of encouraging good weight transfer practices. We pantomime leaning forward on the brakes, then say that gives more grip to the front and we can turn harder, but I see it as the first part of a whole arc, where we transfer the weight forward then gradually to the side and to the rear, running along the outer edge of the friction circle.

I would guess the hesitancy to teach it at a beginner level is that trail braking often shows up described as a technique to carry speed further into a corner rather than a way of smoothly shifting your vehicle's weight and minimizing disturbances to the chassis. A beginner thinking that they need to carry speed further into the corner is likely to be late on the brakes and try to steer without bleeding off brake pressure. Then they'd likely be off line, turning in too late and messing up their line. (Also the 'always brake in a straight line' may predate modern ABS systems that have lowered the punishment of unskillfully mixing brakes and steering.)

I think we could maybe add a few more points around the circle to our discussion of weight transfer, but I was told by a previous CDI that discussion of the friction circle tends to go over most PDS student's heads.

At the volunteer party Dan Chambers was talking about his secrets to going fast at Big Willow and he repeatedly emphasized that how you come off the brakes is as important as how you apply them. Perhaps a compromise is to discuss smooth brake release, and as the students perform well then discuss shifting the braking so that the release is continuing as turn in begins. Big track really made the nuances of weight shift easier to grasp for me, as you spend more time at the edges of the friction circle it becomes easier to see the negative effect of being jerky with your inputs/weight transfer.

Of course there are many instructors with much more experience than I that would be interesting to hear from.

[Tom Helvey]

I think PCA wants to emphasize safety above anything else.
Teaching straight line braking should never cause a novice driver to have any problems getting around a track.
Like heel-toe, trail braking should be taught once a driver has demonstrated that they can safely drive the track (Signed off for Solo).
Trail braking is absolutely essential for getting the fastest times, but that's not what we teach our novice drivers. We want everyone to drive safely first of all.
Maybe we need an advanced HPDE?

[afilsinger]

At the volunteer party Dan Chambers was talking about his secrets to going fast at Big Willow and he repeatedly emphasized that how you come off the brakes is as important as how you apply them. Perhaps a compromise is to discuss smooth brake release, and as the students perform well then discuss shifting the braking so that the release is continuing as turn in begins. Big track really made the nuances of weight shift easier to grasp for me, as you spend more time at the edges of the friction circle it becomes easier to see the negative effect of being jerky with your inputs/weight transfer.

Dan really hit the nail on the head about brake release being equally important to the application. In my experience, when I teach braking I tell advanced students to focus on where they want to finish braking, not where they want to start braking. By changing your focus to your release point, your body will automatically have a better brake application, and you will start to figure out bleeding the pressure out nicely. This kills 3 birds with one stone - It tunes your application to be a rapid application to peak pressure, it tunes your brake release to be a gradual bleed as you constantly adjust pressure to not over slow and it encourages the driver to keep eyes up as you need to be looking ahead to find your release point.

This gets really easy to teach when drivers have data systems in the car. Brake pressure sensors make this easy to visualize, but you can use longitudinal G as a proxy for braking as well. An ideal brake trace has a sharp application to full pressure, and a fairly even trail back to 0 pressure. Many drivers struggle with the initial application - often easing in, then panicking and adding more pressure. This upsets the car and shows that you could have gone later into the brake zone. I would much rather see a driver have a perfect application and over slow, than see them panicking and adding pressure. Not only is it safer, but it is easier to correct. The other common brake trace I see is drivers hitting peak pressure, thinking they have slowed enough and bringing pressure out, then realizing they are a little hot and adding the pressure back in again. Again upsetting the balance of the car. Both of these scenarios are easily overcame by focusing on where you want to finish braking, instead of where you want to start.

Like heel-toe, trail braking should be taught once a driver has demonstrated that they can safely drive the track (Signed off for Solo).

I disagree with you that heel-toe is an advanced skill. In my opinion heel-toe should be a pre-requisite to driving a manual car on track. It is a basic fundamental that mitigates a safety issue AND mechanical problems. If you don't rev match your downshifts, you run the risk of binding up the drive wheels and spinning the car. Rev matched downshifts eliminate this by keeping the car balanced and happy, as well as limiting mechanical strain on the driveline.

[LUCKY DAVE]

Like in politics, the current "truth" depends on the mindset of the current CDI.
During my tenure as CDI I always taught trail braking, not only during in-car instruction but to the students at the school starting with the basic lecture, and I urged the other instructors to do the same.
Why? My rationale is that every driver on the road routinely trail brakes during day-to-day driving, why not teach them recognize what they're already doing and learn to do it correctly?
Of course very student is different. and must be taught at their own pace. Riding with Alex F on the early/mid/late apex exercise I was teaching trail braking by the second lap, as he understood the point of the exercise by the end of the first one. Not all students are like this haha.

Others had different opinions to mine. Some ran in circles screaming at the thought that any driver of less than F1 ability could learn to trail brake, others were stuck in the "we teach old 911 techniques only" mindset.
Every standing CDi has the ability to set the standards of what is taught. You think you have improved the syllabus to reflect the dynamics of the modern cars students actually drive, then the next CDI comes along and has a different idea.
And that's just fine. It's a volunteer club, remember?

[dcarusillo]

Excellent discourse. Nice input from our Instructors as well. Much Appreciated.

Alex makes important points re heel/toe. For those reasons heel toe is an essential component of driving a manual tranny, ......anywhere.

Trail braking is absolutely essential for getting the fastest times, but that's not what we teach our novice drivers. We want everyone to drive safely first of all.

I never really understood this concept of trail braking not being safe. I understand the increased possibility of flat spotting a tire....in a non ABS car.
But given what most Members now "race" (modern electronic hammers) why is gradually releasing the pedal "unsafe"?

[afilsinger]

I never really understood this concept of trail braking not being safe. I understand the increased possibility of flat spotting a tire....in a non ABS car.
But given what most Members now "race" (modern electronic hammers) why is gradually releasing the pedal "unsafe"?

I think the notion of trail braking being unsafe comes from peoples propensity to spin while learning to trail brake. "new" drivers are occasionally unprepared for the rear to rotate as quickly as it can, and spin out while learning how to balance the car while trailing the brake in. This could cause incidents IF someone is following too closely as if they were in the advanced group, or a race. If everyone is behaving as they should in a DE/low intermediate point by environment, teaching trail braking should be a non-event for all involved, especially with so many new cars having intrusive nannies to mask your mistakes for you.

TL/DR: I agree with Dan that we should be teaching this. I tend to teach trail braking fairly early on, once I am confident my students can understand and apply it as a side effect of how I teach them how to brake.

[dcarusillo]

TL/DR: I agree with Dan that we should be teaching this. I tend to teach trail braking fairly early on,

Amen Alex, and I love to read your ideas!

[Tom Helvey]

Excellent discourse. Nice input from our Instructors as well. Much Appreciated.

Alex makes important points re heel/toe. For those reasons heel toe is an essential component of driving a manual tranny, ......anywhere.

Trail braking is absolutely essential for getting the fastest times, but that's not what we teach our novice drivers. We want everyone to drive safely first of all.

I never really understood this concept of trail braking not being safe. I understand the increased possibility of flat spotting a tire....in a non ABS car.
But given what most Members now "race" (modern electronic hammers) why is gradually releasing the pedal "unsafe"?

There are some corners where trail braking by default can be dangerous, turn 6 at LS for example. (I always trail brake there anyway to some degree)
We don't teach drivers to be fast, we teach them to be safe and smooth.
It really comes down to how much car control we can teach effectively at a DE event.
If you have a student who can benefit from understanding trail braking, by all means, teach it.
If you have a student who is struggling to make it around the track for the first time, you might want to skip the topic.

[Tom Helvey]

I disagree with you that heel-toe is an advanced skill. In my opinion heel-toe should be a pre-requisite to driving a manual car on track. It is a basic fundamental that mitigates a safety issue AND mechanical problems. If you don't rev match your downshifts, you run the risk of binding up the drive wheels and spinning the car. Rev matched downshifts eliminate this by keeping the car balanced and happy, as well as limiting mechanical strain on the driveline.

My second DE coach was Bruce Wing, when I drove with him I had no idea whatsoever what heel-toe was.
But, he mentioned that it was something I should learn and work on.
I did some research after the event and taught myself how to do it, (I still mess it up)
You can't learn how to do it at the track, you need to practice and do it all the time to master it.
You can't assume that any DE student has any knowledge whatsoever about that technique and it should not be a requirement for novice drivers.

[Tom Helvey]

I was a student and a novice a very short time ago. I'm still a student and a novice.
I would have been overwhelmed if anyone tried to teach me either trail braking or heel-toe my first or second time on the track.
As it was, I was still overwhelmed.
Depending on the student, an introduction to trail braking may be appropriate for the second or third event they attend.
Braking on a track is pretty much exactly the opposite of braking on the street.
On the street, drivers are trained to gradually increase brake pressure and brake smoothly until they come to a stop.
On the track, drivers need to learn how to brake with hard initial pressure without exceeding the ABS threshold, this is not intuitive, but it's a technique that should be taught early.
We teach straight line braking because it's the easiest way to introduce new drivers to braking on a track.
Very few will initially understand the concept of driving at WOT until the braking zone, then braking hard. I know I didn't.
We usually sign drivers off for solo after 4 events so we don't get a lot of time to teach them mastery.
That decision is based primarily on whether or not the driver is a hazard to themselves or others on the track. Fine tuning technique is not really a consideration.
I guarantee you that every new driver wants to be signed off for solo as soon as they have driven their first yellow group event.
Everyone has completely valid points but we need to teach new drivers to walk before we teach them to fly.
Making the learning curve too steep will just discourage them.

[Jad]

I think this discussion shows that even experienced drivers are confused by what trail braking really is. I don't think I have had a new student that would benefit from trail braking in the 25 years of instructing. And I can't remember my last new student with a stick???

Speed and lap time is gained at corner exit and line, NOT corner entry. Teaching trail braking is only going to make newbies enter the corner too fast, miss the apex and maybe think they are fast. They need to focus on the big areas and saving seconds, not the details, saving 10ths.

Cars do not brake well in a corner, though modern traction control does a great job of hiding that fact. You can often brake LATER if you brake hard in a straight line to slow the car, then as Alex said, the key is how you come off the brakes. You need to gently roll off the brakes as you turn to the apex AFTER your straight line braking to help with rotation by keeping the front tires loaded appropriately. Riding this edge of traction is also an advanced skill that takes practice to feel that is only getting harder to learn as the modern cars hide this limit by cutting things off way before the limit and dragging only one brake to stop the desired rotation.

One of the main reasons I don't teach much anymore is that all of these technique and results can be demonstrated and learned in a old 911 or 944 or Miata, but I have no idea how to even begin to teach that stuff to a computer controlled GT3 or any other new Porsche. New systems work so smoothly, new drivers have no idea the cars is driving, not them. Even with traction control "off" it usually kicks in when you touch the brakes and I certainly can't keep track from year to year and model to model if you can turn it off, how much, and what mode is best as Porsche really does not want you to know the truth about all that.

I think the best reason to teach some of this stuff is to build excitement to keep drivers coming back, not to improve lap times or make them safer.

When my son takes the DE class at Chuckwalla in 2 weeks, I will NOT be teaching him trail braking or heal toe. If he loves racing, those skills will come much later for us. Just my $.02.

[LUCKY DAVE]

Cars do not brake well in a corner, though modern traction control does a great job of hiding that fact. You can often brake LATER if you brake hard in a straight line to slow the car, then as Alex said, the key is how you come off the brakes. You need to gently roll off the brakes as you turn to the apex AFTER your straight line braking to help with rotation by keeping the front tires loaded appropriately. Riding this edge of traction is also an advanced skill that takes practice to feel that is only getting harder to learn as the modern cars hide this limit by cutting things off way before the limit and dragging only one brake to stop the desired rotation.

One of the main reasons I don't teach much anymore is that all of these technique and results can be demonstrated and learned in a old 911 or 944 or Miata, but I have no idea how to even begin to teach that stuff to a computer controlled GT3 or any other new Porsche. New systems work so smoothly, new drivers have no idea the cars is driving, not them. Even with traction control "off" it usually kicks in when you touch the brakes and I certainly can't keep track from year to year and model to model if you can turn it off, how much, and what mode is best as Porsche really does not want you to know the truth about all that.

I think the best reason to teach some of this stuff is to build excitement to keep drivers coming back, not to improve lap times or make them safer.

Jad, you are exactly right. And I disagree with you.

I teach trail braking because my students aren't always going to be driving their new(ish) Porsche. They may be driving a rented box truck on a snowy mountain road when they move to Colorado, or out for a foolish romp in their buddy's hot rod '64 Falcon, or take a few laps in their other buddy's 3.2 Carrera. They may ride their motorcycle up to Julian. They may get in a hurry on a fork lift (don't laugh, trail braking works on everything).
We should be teaching works-in-anything driving techniques, not just Porsche specific driving techniques.

When I learned to fly 30+ years ago, my instructor insisted that we take as different an airplane as we could find for every lesson. Six seat transportation airplanes, feeble powered tube'n fabric tail draggers, big HP aerobatic monsters, high wing, low wing, twin engines, retractable gear, gliders, etc. I flew into small airports, huge airports, farmers fields, dry lakes in the desert, and landed on concrete, asphalt, dirt, grass, runways long/wide, very short/narrow, you name it.
It was great training, by the time I got my license I had the confidence and experience to fly anything, anywhere.
As much as possible we should do the same for our 4 wheel students, not just teach them to fly "one plane".

[Tom Helvey]

They may be driving a rented box truck on a snowy mountain road when they move to Colorado

I lived in Wisconsin all my life (Black ice winters) and I've owned a few box trucks (bands). A 6000 lb ten year old used U-Haul hauling 10,000 lb of gear is the last thing you'd ever want to
try to trail brake in a blizzard.