Trail Braking Instruction Strategies
07-05-2007, 01:57 PM
#1
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Trail Braking Instruction Strategies
Hey Gurus;
At the risk of starting a real war on this most incendiary topic
, I will ask anyway.
To those of you who have quantified a procedure for doing so, or who have a solid understanding of the mechanics of it from your own driving, how do you teach TB?
I ask this because it is I who am my own student here, and the student is struggling with it. I fully realize a few basic things. 1) It is a worthwhile trick to have in your bag in some instances. Time is available to be shaved off the clock by using it in the right places. 2) Braking is likely the hardest skill to perfect when driving swiftly. 3) TB is counter to what most of us were taught in DE, and for that reason alone is difficult to reprogram.
So, I was fiddling about with it a bit at the 48 Hours. I found that I simply did not get it to work, except of a couple of rare instances where it seemed to click perfectly. In trying to analyze why I was struggling with it, I came up with a couple of answers.
First, I have not been a Conscious Incompetant driver for many years. Having to think about what I was attempting was a trip back to the early days, and an interesting exercize in relating to student angst over what are seemingly simple tasks to you and I.
Second, I am almost totally a Feel driver. I do nothing methodically or mechanically. I use absolutely NO reference points and the only thing I really pay attention to are my mirrors, my tach, and my subconscious, which is hard wired to my ****-o-meter. I am coming to the realization that what I need to do is first establish markers for where I do my corner setup so that I can then tweak them.
All this quantification is anathema to me, for the most part, which is why I think I am finding it so difficult.
What say you, esteemed colleagues?
At the risk of starting a real war on this most incendiary topic
, I will ask anyway.To those of you who have quantified a procedure for doing so, or who have a solid understanding of the mechanics of it from your own driving, how do you teach TB?
I ask this because it is I who am my own student here, and the student is struggling with it. I fully realize a few basic things. 1) It is a worthwhile trick to have in your bag in some instances. Time is available to be shaved off the clock by using it in the right places. 2) Braking is likely the hardest skill to perfect when driving swiftly. 3) TB is counter to what most of us were taught in DE, and for that reason alone is difficult to reprogram.
So, I was fiddling about with it a bit at the 48 Hours. I found that I simply did not get it to work, except of a couple of rare instances where it seemed to click perfectly. In trying to analyze why I was struggling with it, I came up with a couple of answers.
First, I have not been a Conscious Incompetant driver for many years. Having to think about what I was attempting was a trip back to the early days, and an interesting exercize in relating to student angst over what are seemingly simple tasks to you and I.
Second, I am almost totally a Feel driver. I do nothing methodically or mechanically. I use absolutely NO reference points and the only thing I really pay attention to are my mirrors, my tach, and my subconscious, which is hard wired to my ****-o-meter. I am coming to the realization that what I need to do is first establish markers for where I do my corner setup so that I can then tweak them.
All this quantification is anathema to me, for the most part, which is why I think I am finding it so difficult.
What say you, esteemed colleagues?
07-05-2007, 02:35 PM
#2
Race Director
One thing you can do it make the car into a understeering pig.
Then try to trail brake some. It will make the car feel SO MUCH BETTER.
Then adjust the car back close to normal.
I am thinking since you drive by feel that it will not feel right to trail brake to get the rear end to rotate. Sounds like you can physically do it, but you just don't feel comfortable doing it. So maybe you will need to do something to make it feel better. One of the reasons I learned to trail brake was my 944 had understeer for a while. TB really helped that. Then I dial out the full throttle corner exit understeer and everthing just came together.
Then try to trail brake some. It will make the car feel SO MUCH BETTER.
Then adjust the car back close to normal.
I am thinking since you drive by feel that it will not feel right to trail brake to get the rear end to rotate. Sounds like you can physically do it, but you just don't feel comfortable doing it. So maybe you will need to do something to make it feel better. One of the reasons I learned to trail brake was my 944 had understeer for a while. TB really helped that. Then I dial out the full throttle corner exit understeer and everthing just came together.
07-05-2007, 02:56 PM
#3
It may also help you to think of the three types of braking:
1 - Straight line braking (threshold)
2 - Turn braking (less brake with steering dialed in)
3 - Trail braking (rotation)
I learned trail braking in Big Bend at Lime Rock. It's a great way to get through the second half of the turn. At the Glen it comes in pretty handy in the Toe, especially if you like to double apex there.
Autocrossing may be a good way to practice it too.
1 - Straight line braking (threshold)
2 - Turn braking (less brake with steering dialed in)
3 - Trail braking (rotation)
I learned trail braking in Big Bend at Lime Rock. It's a great way to get through the second half of the turn. At the Glen it comes in pretty handy in the Toe, especially if you like to double apex there.
Autocrossing may be a good way to practice it too.
07-05-2007, 03:18 PM
#5
Rennlist Member
An instructor explained it to me this way: brake hard into the turn and then ease off the brakes smoothly. The faster you come off the brakes the faster the rotation is, and you can modulate the rotation speed. Tighter and slower corners are better for this technique. Properly done, the car feels a bit disconnected, rather like it's a boat and your brake pedal is connected to the rudder. The car is controllable, but it can be disconcerting at first.
07-05-2007, 03:24 PM
#6
John,
Learning how to trailbrake (really trailbrake) can be difficult, at least it is for me.
I understand that you drive by feel, but if you have yet to "feel" what it is like to trailbrake correctly (I don't think many do at DEs, even when they say they do), it would probably helpful to jump in someone's car who REALLY trailbrakes -- like Chris Cervelli -- or . . . you need to force yourself to be methodical.
One of the keys to trailbraking is to make a smooth transition from braking to throttle, and making this transition well into the corner (as opposed to shortly after turn-in). Another key is to learn what to do with the steering wheel when you begin turning the car more with the pedals. It is all a question of timing and feel.
In order to do this, you, by definition, must increase your corner entry speed: If you enter the corner at the same speed you do when you release the brakes shortly after turn in, you will come to a stop at the apex once you really trailbrake.
However, entering a corner even faster than normal when you are trying to get a new technique down can be "interesting."
I would pick one corner to practice with, and make it one that is relatively low speed and obstruction free. Then, I would work on braking earlier and much more gently (less) so that your transitions from gas to brake and then back to gas are not so dramatic.
Start out with your normal entry speed, and make yourself stay on the brakes to the apex. You will see how you die in the middle of the corner. Then, start picking up entry speed a LITTLE each lap until you are back at a good mid-corner speed.
If you do it right, you will begin to feel the car rotate, and you will time that rotation correctly (i.e., not too early in the corner and not too late), so that you naturally will transition very smoothly from brakes to gas to get the rear end planted again. When done correctly, you likely will not be able to go from gas to full throttle immediately, and your wheel will be open, or nearly open, at the apex or shortly thereafter.
For me, it is hard not to let off the brakes a little too early and then squeeze on them more when I need more rotation. Done correctly, it will be a relatively smooth transition from more braking to less braking, not multiple rotations due to needing to rotate the car more mid-turn. Likewise, it is sometimes hard to squeeze on the brakes more when I need more rotation rather than turning in the wheel more. The wheel is there just to point the car in the right direction for the rotation . . . much of the rotation is done with the right feet. If you find yourself in mid-corner with a whole lot of speed and not quite enough rotation, it is also difficult to fight the temptation to squeeze the brakes a little more AND turn the wheel in, which obviously will result in instability. As with all things, practice makes perfect.
It is all a question of timing and feel. Until you get it right, you probably will have to sacrifice overall speed. That said, with enough discipline and learning the technique correctly, I personally am confident that most of us will be faster in the end.
Hope these hints from a fellow student help.
Learning how to trailbrake (really trailbrake) can be difficult, at least it is for me.
I understand that you drive by feel, but if you have yet to "feel" what it is like to trailbrake correctly (I don't think many do at DEs, even when they say they do), it would probably helpful to jump in someone's car who REALLY trailbrakes -- like Chris Cervelli -- or . . . you need to force yourself to be methodical.
One of the keys to trailbraking is to make a smooth transition from braking to throttle, and making this transition well into the corner (as opposed to shortly after turn-in). Another key is to learn what to do with the steering wheel when you begin turning the car more with the pedals. It is all a question of timing and feel.
In order to do this, you, by definition, must increase your corner entry speed: If you enter the corner at the same speed you do when you release the brakes shortly after turn in, you will come to a stop at the apex once you really trailbrake.
However, entering a corner even faster than normal when you are trying to get a new technique down can be "interesting."
I would pick one corner to practice with, and make it one that is relatively low speed and obstruction free. Then, I would work on braking earlier and much more gently (less) so that your transitions from gas to brake and then back to gas are not so dramatic.
Start out with your normal entry speed, and make yourself stay on the brakes to the apex. You will see how you die in the middle of the corner. Then, start picking up entry speed a LITTLE each lap until you are back at a good mid-corner speed.
If you do it right, you will begin to feel the car rotate, and you will time that rotation correctly (i.e., not too early in the corner and not too late), so that you naturally will transition very smoothly from brakes to gas to get the rear end planted again. When done correctly, you likely will not be able to go from gas to full throttle immediately, and your wheel will be open, or nearly open, at the apex or shortly thereafter.
For me, it is hard not to let off the brakes a little too early and then squeeze on them more when I need more rotation. Done correctly, it will be a relatively smooth transition from more braking to less braking, not multiple rotations due to needing to rotate the car more mid-turn. Likewise, it is sometimes hard to squeeze on the brakes more when I need more rotation rather than turning in the wheel more. The wheel is there just to point the car in the right direction for the rotation . . . much of the rotation is done with the right feet. If you find yourself in mid-corner with a whole lot of speed and not quite enough rotation, it is also difficult to fight the temptation to squeeze the brakes a little more AND turn the wheel in, which obviously will result in instability. As with all things, practice makes perfect.
It is all a question of timing and feel. Until you get it right, you probably will have to sacrifice overall speed. That said, with enough discipline and learning the technique correctly, I personally am confident that most of us will be faster in the end.
Hope these hints from a fellow student help.
07-05-2007, 04:44 PM
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On corner entry, the reduction of braking and the addition of steering produces trail-braking. The nose of the car goes down under hard braking and stays down as the driver blips for the downshift and as he or she turns the car. The longitudinal transfer of weight from the car's rear to the car's front loads the car's nose as it turns and keeps the car stable under hard braking in the corner. Moreover, trail-braking allows the car to rotate ("tbr": trail-brake rotation)--as the driver trails off the brake--to oversteer, which enables the driver to open the throttle at a better angle to the apex.
The author of Going Faster, Carl Lopez, identifies two stategies for using the brake pedal in trail-braking: (i) "constantly relax pedal pressure as the car approaches the throttle application point," and (ii) relax the brake pedal effort to a certain level and hold in there." (i), Lopez notes, involves "the process of trailing away from the brake as the car decelerates while turning," while (ii) "is particularly effective in corner entries where the brake-turn segment is particularly long."
Lopez also points out that "the length of the brake-throttle transition will affect how the car sets its cornering grip angle." A brake to throttle transition which is slow keeps the reduction in braking effort "in sync with the changes in front to rear loading"; a sharp, abrupt reduction in braking, however, will "[deliver] instant cornering traction to the front of the car by suddenly giving all of the front tires' grip over to cornering force. The car is likely to point aggressively toward the apex, increasing the car's yaw angle."
A driver who uses trail-braking--brake-turning--effectively can control his or her car's cornering force with degrees of brake modulation. The level of brake turning, Lopez adds, is contingent upon the type of corner in which the technique will be applied. A Type 1 corner--one which places emphasis on exit speed--will require less trail-braking and earlier throttle application. Entry speed matters more in a Type 2 corner, and consequently a longer period of trail-braking can be used effectively to reduce the time the driver spends from the turn-in point to the apex. A Type 3 corner, one for which the driver compromises entry speed and line for exit speed, will make fewer demands of a driver's ability to brake-turn his or her car.
There are many drivers who use two brake (and throttle) pedal positions: no pedal pressure and full pedal pressure. First, I ask a student to demonstrate consistently effective threshold braking ("10" is the threshold of lockup; I ask a student to initiate threshold braking at "7" and then to increase braking quickly through "8" and "9" to "10"). I encourage the student to make his or her car lose the correct amount of speed quickly. When the student has demonstrated that he or she has the ability to use threshold braking, I ask the student to (i) reduce brake pressure smoothly as he or she turns the car towards the corner's apex, (ii) transition smoothly from the brake pedal to the throttle, and (iii) accelerate smoothly through the corner. Initially, I have students practice trail-braking in corners with ample run-off (Turn 1 at WGI, for example) and at reduced speeds. I identify for the student his or her car's longitudinal and lateral weight transfer as he or she practices brake pressure reduction, steering application, the brake to throttle transition, and throttle application. As students develop their skills, degrees of competence, and levels of confidence, I encourage them to apply their trail-braking skills in other corners where brake-turning is advantageous.
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The author of Going Faster, Carl Lopez, identifies two stategies for using the brake pedal in trail-braking: (i) "constantly relax pedal pressure as the car approaches the throttle application point," and (ii) relax the brake pedal effort to a certain level and hold in there." (i), Lopez notes, involves "the process of trailing away from the brake as the car decelerates while turning," while (ii) "is particularly effective in corner entries where the brake-turn segment is particularly long."
Lopez also points out that "the length of the brake-throttle transition will affect how the car sets its cornering grip angle." A brake to throttle transition which is slow keeps the reduction in braking effort "in sync with the changes in front to rear loading"; a sharp, abrupt reduction in braking, however, will "[deliver] instant cornering traction to the front of the car by suddenly giving all of the front tires' grip over to cornering force. The car is likely to point aggressively toward the apex, increasing the car's yaw angle."
A driver who uses trail-braking--brake-turning--effectively can control his or her car's cornering force with degrees of brake modulation. The level of brake turning, Lopez adds, is contingent upon the type of corner in which the technique will be applied. A Type 1 corner--one which places emphasis on exit speed--will require less trail-braking and earlier throttle application. Entry speed matters more in a Type 2 corner, and consequently a longer period of trail-braking can be used effectively to reduce the time the driver spends from the turn-in point to the apex. A Type 3 corner, one for which the driver compromises entry speed and line for exit speed, will make fewer demands of a driver's ability to brake-turn his or her car.
There are many drivers who use two brake (and throttle) pedal positions: no pedal pressure and full pedal pressure. First, I ask a student to demonstrate consistently effective threshold braking ("10" is the threshold of lockup; I ask a student to initiate threshold braking at "7" and then to increase braking quickly through "8" and "9" to "10"). I encourage the student to make his or her car lose the correct amount of speed quickly. When the student has demonstrated that he or she has the ability to use threshold braking, I ask the student to (i) reduce brake pressure smoothly as he or she turns the car towards the corner's apex, (ii) transition smoothly from the brake pedal to the throttle, and (iii) accelerate smoothly through the corner. Initially, I have students practice trail-braking in corners with ample run-off (Turn 1 at WGI, for example) and at reduced speeds. I identify for the student his or her car's longitudinal and lateral weight transfer as he or she practices brake pressure reduction, steering application, the brake to throttle transition, and throttle application. As students develop their skills, degrees of competence, and levels of confidence, I encourage them to apply their trail-braking skills in other corners where brake-turning is advantageous.
________________
PCA National Instructor
GVC-BMW CCA Instructor
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07-05-2007, 04:59 PM
#8
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Practice at a track you are very comfortable. Back to Summit T1 is always a good place. Look first at you braking points, then change your focus to where you want to STOP BRAKING into the turn. Visualize a braking line that is no longer straight, but an arcing radius to the apex. Work on the braking release into the turn. I am no expert, but this is how I run the drill on new tracks and when I am data logging a track for improvements. Your foot will follow your eyes as does the hands on the wheel. BTW, watch your closing speeds with the car in front, you may find alot less room as you get better at this.
07-06-2007, 12:42 AM
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Turn 3 at Homestead comes to mind in this discussion as entry speed in this corner is critical. The best way I have found to go into this corner sums up my thoughts on trail braking.
Turn 3 is a 90 degree (approx) left hander with about 75 feet (approx) after the apex to a right turn entry into a down hill semi-carousel. Turn 3, TO ME, is all about setting up the entry to the carousel. Turn 3 is a SLOW corner and eats up some serious time. So....the faster through 3 the better BUT, you better not blow the entry to the carousel because you'll either give the time back there by being out of position or by spinning. So....what to do?
Many people simply sacrifice turn 3. I look at every slow corner as an opportunity. Sorta like eagling a par 5. Sure, you can lay up and hit a wedge close and try to make a putt OR you can go for it in two. Going for turn three and the carousel means trying to carry as much speed as possible. Due to the angle of the turn, the only way to do this is trail brake.
Instead of going all the way out to the right, slowing way down and turning before application of the throttle, I come in maybe 4-5 feet from the right edge of the pavement and brake hard and modulate off until the car is rotated about 60 degrees. Applying the throttle at this point brings the rear around and I'm pointed straight for my spot for the carousel entry.
To be sure, I've blown this corner several times, I've slid A LOT but when I get it right, I know that there aren't many in my similar car who could be going much faster than I am at the apex. The only way to be at that speed is to trail brake.
Turn 3 is a 90 degree (approx) left hander with about 75 feet (approx) after the apex to a right turn entry into a down hill semi-carousel. Turn 3, TO ME, is all about setting up the entry to the carousel. Turn 3 is a SLOW corner and eats up some serious time. So....the faster through 3 the better BUT, you better not blow the entry to the carousel because you'll either give the time back there by being out of position or by spinning. So....what to do?
Many people simply sacrifice turn 3. I look at every slow corner as an opportunity. Sorta like eagling a par 5. Sure, you can lay up and hit a wedge close and try to make a putt OR you can go for it in two. Going for turn three and the carousel means trying to carry as much speed as possible. Due to the angle of the turn, the only way to do this is trail brake.
Instead of going all the way out to the right, slowing way down and turning before application of the throttle, I come in maybe 4-5 feet from the right edge of the pavement and brake hard and modulate off until the car is rotated about 60 degrees. Applying the throttle at this point brings the rear around and I'm pointed straight for my spot for the carousel entry.
To be sure, I've blown this corner several times, I've slid A LOT but when I get it right, I know that there aren't many in my similar car who could be going much faster than I am at the apex. The only way to be at that speed is to trail brake.
07-06-2007, 01:43 AM
#12
Race Director
When I went to the Porsche School at Barber Motorsports we worked on trail braking a few corners. I learned a lot about the car on the skid pad and applied it to the track.
I drive Sebring for my DE's and during the green and some of the blue group runs I was not allowed to trail brake. Last weekend my instructor started to get me to trail brake some corners and I did pretty well.
I will be back in solo group at Sebring in a few weeks and plan on working on this further. What corners do you all that know Sebring very well trail brake.
So far I am trail braking turn 1, 7, 10, 13, 17 (1st apex). Turn 7 seems the safest to practice on.
Thanks in advance for any advice and thoughts.
Mike
I drive Sebring for my DE's and during the green and some of the blue group runs I was not allowed to trail brake. Last weekend my instructor started to get me to trail brake some corners and I did pretty well.
I will be back in solo group at Sebring in a few weeks and plan on working on this further. What corners do you all that know Sebring very well trail brake.
So far I am trail braking turn 1, 7, 10, 13, 17 (1st apex). Turn 7 seems the safest to practice on.
Thanks in advance for any advice and thoughts.
Mike
07-06-2007, 06:13 AM
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Just a thought, get into a FWD car for a bit of practice. They require trail braking in order to turn in at all well. It will quickly become second nature, and you will then be able to use the new found skill in your Porker to good effect.
07-06-2007, 09:12 AM
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John,
After I got my datalogger last year, one of the first things I noticed was that I was not trailbraking as much as I thought I was (I was fully off the brakes shortly after turn-in). What I did was to adjust the car for a bit more understeer and pick a 3rd gear corner that I thought would really benefit from trailbraking (in this case, T8 at Tremblant). I, like you do not use any physical reference points when driving, so what I did was, as I was approaching T8 and felt I need to start braking, I would pause for a half second or so, and then brake with the usual pressure. This resulted in me having a higher than normal speed at my turn in point and allow me to carry some braking pressure (light at first) into the corner and bleed it off as the **** got lighter. It takes a while to get really comfortable with it, but it is really a useful tool in some of the slower corners. When you get to Calabogie in a couple of weeks, there is tight right hand corner there called "The Beak". You will see a lot of guys taking a slow, late apex into that turn to get setup for the left that follows it. I've found that the quick way is an earlier turn-in and trail brake in deep. It allows me to travel a shorter distance and maintain a higher initial entry speed.
After I got my datalogger last year, one of the first things I noticed was that I was not trailbraking as much as I thought I was (I was fully off the brakes shortly after turn-in). What I did was to adjust the car for a bit more understeer and pick a 3rd gear corner that I thought would really benefit from trailbraking (in this case, T8 at Tremblant). I, like you do not use any physical reference points when driving, so what I did was, as I was approaching T8 and felt I need to start braking, I would pause for a half second or so, and then brake with the usual pressure. This resulted in me having a higher than normal speed at my turn in point and allow me to carry some braking pressure (light at first) into the corner and bleed it off as the **** got lighter. It takes a while to get really comfortable with it, but it is really a useful tool in some of the slower corners. When you get to Calabogie in a couple of weeks, there is tight right hand corner there called "The Beak". You will see a lot of guys taking a slow, late apex into that turn to get setup for the left that follows it. I've found that the quick way is an earlier turn-in and trail brake in deep. It allows me to travel a shorter distance and maintain a higher initial entry speed.
07-06-2007, 09:14 AM
#15
Originally Posted by sjanes
John,
After I got my datalogger last year, one of the first things I noticed was that I was not trailbraking as much as I thought I was (I was fully off the brakes shortly after turn-in).
After I got my datalogger last year, one of the first things I noticed was that I was not trailbraking as much as I thought I was (I was fully off the brakes shortly after turn-in).