When to introduce rotating the car to a student?
03-31-2018, 11:37 AM
#61
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I do believe that most folks can make big gains by getting a good jump out of 5A and carrying as much speed through esses and south bend and hustling all the way to 12. I think there are whole seconds to be gained for most intermediate driver between 5A and 11. I defer to your experience.
To the OP, I feel that once a driver understands that the brakes are not only for braking but weight transfer, it would be time to introduce the concept. Start on a skit pad or in a low speed section of a track where there are no adverse consequences when you get it wrong (T7 at Sebring, Lefthander at Lime Rock, T11/Oak Tree at VIR, Toe of the Boot at WGI, T9/T10 at NJMP Thunderbolt, T1 and T6 at Summit Point). I don't think the Bus Stop (Inner Loop) at Watkins Glen is a good example as it is all about steering speed once you clip the initial curbing in order to allow you to get on full throttle earliest. The car in the video is very slow there. Good drivers in similar cars are at 85 mph min speed there.
03-31-2018, 12:34 PM
#62
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I'm not an instructor and don't ride right seat so I can't contribute to the OP's original question much, but I know a bit about VIR (thanks to Peter) and the Climbing Esses are the worst part to be looking for lap time improvement. I can be 10 - 20 mph faster than my competitors there and I can tell you that it doesn't make a difference because you are not spending a lot of time in that section. Most people over-slow T11, which requires them to coast (or accelerate) to T12. The fast drivers will brake through T11 all the way to the turn in point for T12 and rotate the car through brake release and that is an area where you can find a massive amount of time as you spend a lot of time in it. Goal is to be on the throttle as early as possible at T12 as you are about to enter the longest straight. The bottom of Hog Pen is very similar, as you can get on throttle earlier than most people think if you are able to rotate the car between 16a and 16b with the elevation change there.
To the OP, I feel that once a driver understands that the brakes are not only for braking but weight transfer, it would be time to introduce the concept. Start on a skit pad or in a low speed section of a track where there are no adverse consequences when you get it wrong (T7 at Sebring, Lefthander at Lime Rock, T11/Oak Tree at VIR, Toe of the Boot at WGI, T9/T10 at NJMP Thunderbolt, T1 and T6 at Summit Point). I don't think the Bus Stop (Inner Loop) at Watkins Glen is a good example as it is all about steering speed once you clip the initial curbing in order to allow you to get on full throttle earliest. The car in the video is very slow there. Good drivers in similar cars are at 85 mph min speed there.
To the OP, I feel that once a driver understands that the brakes are not only for braking but weight transfer, it would be time to introduce the concept. Start on a skit pad or in a low speed section of a track where there are no adverse consequences when you get it wrong (T7 at Sebring, Lefthander at Lime Rock, T11/Oak Tree at VIR, Toe of the Boot at WGI, T9/T10 at NJMP Thunderbolt, T1 and T6 at Summit Point). I don't think the Bus Stop (Inner Loop) at Watkins Glen is a good example as it is all about steering speed once you clip the initial curbing in order to allow you to get on full throttle earliest. The car in the video is very slow there. Good drivers in similar cars are at 85 mph min speed there.
Excellent info!
03-31-2018, 01:45 PM
#63
I'm not an instructor and don't ride right seat so I can't contribute to the OP's original question much, but I know a bit about VIR (thanks to Peter) and the Climbing Esses are the worst part to be looking for lap time improvement. I can be 10 - 20 mph faster than my competitors there and I can tell you that it doesn't make a difference because you are not spending a lot of time in that section. Most people over-slow T11, which requires them to coast (or accelerate) to T12. The fast drivers will brake through T11 all the way to the turn in point for T12 and rotate the car through brake release and that is an area where you can find a massive amount of time as you spend a lot of time in it. Goal is to be on the throttle as early as possible at T12 as you are about to enter the longest straight. The bottom of Hog Pen is very similar, as you can get on throttle earlier than most people think if you are able to rotate the car between 16a and 16b with the elevation change there.
To the OP, I feel that once a driver understands that the brakes are not only for braking but weight transfer, it would be time to introduce the concept. Start on a skit pad or in a low speed section of a track where there are no adverse consequences when you get it wrong (T7 at Sebring, Lefthander at Lime Rock, T11/Oak Tree at VIR, Toe of the Boot at WGI, T9/T10 at NJMP Thunderbolt, T1 and T6 at Summit Point). I don't think the Bus Stop (Inner Loop) at Watkins Glen is a good example as it is all about steering speed once you clip the initial curbing in order to allow you to get on full throttle earliest. The car in the video is very slow there. Good drivers in similar cars are at 85 mph min speed there.
To the OP, I feel that once a driver understands that the brakes are not only for braking but weight transfer, it would be time to introduce the concept. Start on a skit pad or in a low speed section of a track where there are no adverse consequences when you get it wrong (T7 at Sebring, Lefthander at Lime Rock, T11/Oak Tree at VIR, Toe of the Boot at WGI, T9/T10 at NJMP Thunderbolt, T1 and T6 at Summit Point). I don't think the Bus Stop (Inner Loop) at Watkins Glen is a good example as it is all about steering speed once you clip the initial curbing in order to allow you to get on full throttle earliest. The car in the video is very slow there. Good drivers in similar cars are at 85 mph min speed there.
VIR has 3 long straights. We all 3 agree that getting out of the preceding corners is crucial to gaining time. From hog pen and oak tree it's pretty straightforward- if you get a good jump you'll gain a lot on the end of each straight because there is no real courage needed on this straights and since they are pretty long, you'll gain good time.
However, I the point that I was really intending make was that the climbing esses (and WGI esses) are a challenge for Intermediate drivers to directly translate good exit into higher top speed through those sections because honestly it's scary to be flat through both of those sections. I have not seen too many videos of an intermediate driver realizing all of the speed they can through those sections.
I am a learner so I appreciate the dialogue. Also, if someone is willing to share data for 2:00 to 2:02 lap in any 300 to 400 hp car, I'd be happy to see how much I am losing in the corners you mention versus how much I lose or gain in the esses.
Here's a link to my best times from the first time I visited the track last year. Fliers start at about 3:45. I agree that I can improve my work through every section especially oak tree. I just contend that those sections are technique versus testicular fortitude.
03-31-2018, 03:00 PM
#64
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03-31-2018, 04:48 PM
#65
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Thunder
Heres a little clip of frank and I battling for 1st position. We were in the 1.59-2.00 during the weekend. As for the climbing esses, i was told to take it as a straight line and flat. So thats what i go for.
The strange noise you hear in the video are my rear shocks canisters that got disconnected during the race and bouncing in my rear trunk.
The ride was harsh lol 😂
Heres a little clip of frank and I battling for 1st position. We were in the 1.59-2.00 during the weekend. As for the climbing esses, i was told to take it as a straight line and flat. So thats what i go for.
The strange noise you hear in the video are my rear shocks canisters that got disconnected during the race and bouncing in my rear trunk.
The ride was harsh lol 😂
03-31-2018, 05:46 PM
#66
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Seb’s line is terrific and his commitment exceptional.
While folks can “go for” flat, in their mind, it makes little difference to do so and fewer still are able to achieve it, even (AND ESPECIALLY) at Seb and Frank’s track record pace...
IMSA GT Drivers BRAKE at entry of TURN 9, AND, of course, for Turn 10...
03-31-2018, 05:52 PM
#67
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Thundermoose, the major difference is not necessarily vMins at various corners between a 2:11 and a 2:06 in the same car. It’s the DURATION of time, hence distance covered, at or around vMin.
To reduce the time at or near vMin for each of VIR’s twenty-two separate radii corners, you have to move the end of the brake zone INTO most of the corners, such that the entry speed allows for the steering input to take off the rest of the speed the brakes haven’t.
Then, you have to be proactive enough with the throttle (and especially with a 300-400 bhp car) to accelerate AND control the exit radius of many of these corners using the THROTTLE, not JUST the steering.
This means that the TURNING moment has to be as short as possible. This means that the CAR has to do some of the “work” turning and THIS is the purpose and best use of “rotation.”
To reduce the time at or near vMin for each of VIR’s twenty-two separate radii corners, you have to move the end of the brake zone INTO most of the corners, such that the entry speed allows for the steering input to take off the rest of the speed the brakes haven’t.
Then, you have to be proactive enough with the throttle (and especially with a 300-400 bhp car) to accelerate AND control the exit radius of many of these corners using the THROTTLE, not JUST the steering.
This means that the TURNING moment has to be as short as possible. This means that the CAR has to do some of the “work” turning and THIS is the purpose and best use of “rotation.”
03-31-2018, 06:26 PM
#68
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Just want to say thank you to the coaches and experienced racers for your detailed posts.
Us folks, that are learning from your experience re-read these posts multiple times.
Happy Easter / Passover to all
David
Us folks, that are learning from your experience re-read these posts multiple times.
Happy Easter / Passover to all
David
03-31-2018, 07:35 PM
#69
OK so lets get a little more technical as long as we're on the topic. To solidify the whole thing in my feeble brain, a couple of questions:
I'm assuming we're taking about this concept: http://racingcardynamics.com/racing-...lateral-force/
So when I'm in a turn with my steering wheel fixed, if I give the car gas (throttle steer) what exactly happens?
I "feel" the back of the car push more toward the outside of the turn. But how does this help me tighten the turn if the tires don't break free and slip sideways?
And I'm assuming trail braking is the other half of the equation?
Is there also changed turn dynamics in exactly the opposite direction as increased throttle with increased brake pressure?
I'm really enjoying this discussion BTW.
I'm assuming we're taking about this concept: http://racingcardynamics.com/racing-...lateral-force/
So when I'm in a turn with my steering wheel fixed, if I give the car gas (throttle steer) what exactly happens?
I "feel" the back of the car push more toward the outside of the turn. But how does this help me tighten the turn if the tires don't break free and slip sideways?
And I'm assuming trail braking is the other half of the equation?
Is there also changed turn dynamics in exactly the opposite direction as increased throttle with increased brake pressure?
I'm really enjoying this discussion BTW.
If you increase throttle and hold the same steering, the slip angle of the rears will increase past the peak and you will go into oversteer. You'll have to countersteer to avoid a spin. Instead, as you increase throttle you'll want to also remove some steering lock. These should trade off evenly as you come out of the corner. As you increase power to the rear wheels they will have less lateral capacity and so you have to also reduce the lateral force that the front tires are imposing on the car an equal amount. Ideally you would want a steady reduction in steering from apex to corner exit with an equally steady increase in power. Realistically it is more of a balancing act (throttle steering) where you will modulate both while having a general trend of more power, less steering. Notice I said increase power which rarely coincides exactly with throttle. For example, as your rpm climbs through corner exit, power will typically increase even if you hold steady throttle. It all depends on your powerband, so you just have to pay attention to your car control cues to see what amount of throttle will be needed at any moment. Also interestingly, while you should be at the edge of oversteer for all of this, the peak slip angle of the rear tires will drop from apex to exit.
A final tip to put all this together is to remember that if you can't get to full throttle at the apex without oversteer then you shouldn't be able to reach full throttle until corner exit. If you are able to get to full throttle prior to exit then try an earlier faster apex until you just reach full throttle right as you straighten out. This little apex finding shortcut doesn't work for all cars, but it does for the vast majority. Hope this helps.
03-31-2018, 08:28 PM
#70
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It doesn't look like this got answered so I'll see if I can help. Let's assume you are very close to or at the limit of the rears as you go to throttle. A car that understeers under full throttle does something else so we'll skip that for now.
If you increase throttle and hold the same steering, the slip angle of the rears will increase past the peak and you will go into oversteer. You'll have to countersteer to avoid a spin. Instead, as you increase throttle you'll want to also remove some steering lock. These should trade off evenly as you come out of the corner. As you increase power to the rear wheels they will have less lateral capacity and so you have to also reduce the lateral force that the front tires are imposing on the car an equal amount. Ideally you would want a steady reduction in steering from apex to corner exit with an equally steady increase in power. Realistically it is more of a balancing act (throttle steering) where you will modulate both while having a general trend of more power, less steering. Notice I said increase power which rarely coincides exactly with throttle. For example, as your rpm climbs through corner exit, power will typically increase even if you hold steady throttle. It all depends on your powerband, so you just have to pay attention to your car control cues to see what amount of throttle will be needed at any moment. Also interestingly, while you should be at the edge of oversteer for all of this, the peak slip angle of the rear tires will drop from apex to exit.
A final tip to put all this together is to remember that if you can't get to full throttle at the apex without oversteer then you shouldn't be able to reach full throttle until corner exit. If you are able to get to full throttle prior to exit then try an earlier faster apex until you just reach full throttle right as you straighten out. This little apex finding shortcut doesn't work for all cars, but it does for the vast majority. Hope this helps.
If you increase throttle and hold the same steering, the slip angle of the rears will increase past the peak and you will go into oversteer. You'll have to countersteer to avoid a spin. Instead, as you increase throttle you'll want to also remove some steering lock. These should trade off evenly as you come out of the corner. As you increase power to the rear wheels they will have less lateral capacity and so you have to also reduce the lateral force that the front tires are imposing on the car an equal amount. Ideally you would want a steady reduction in steering from apex to corner exit with an equally steady increase in power. Realistically it is more of a balancing act (throttle steering) where you will modulate both while having a general trend of more power, less steering. Notice I said increase power which rarely coincides exactly with throttle. For example, as your rpm climbs through corner exit, power will typically increase even if you hold steady throttle. It all depends on your powerband, so you just have to pay attention to your car control cues to see what amount of throttle will be needed at any moment. Also interestingly, while you should be at the edge of oversteer for all of this, the peak slip angle of the rear tires will drop from apex to exit.
A final tip to put all this together is to remember that if you can't get to full throttle at the apex without oversteer then you shouldn't be able to reach full throttle until corner exit. If you are able to get to full throttle prior to exit then try an earlier faster apex until you just reach full throttle right as you straighten out. This little apex finding shortcut doesn't work for all cars, but it does for the vast majority. Hope this helps.
Does this mean you feather (pulsate) the throttle increase or actual smooth steady rpm increase until you get desired amount of rear tire slip?
03-31-2018, 08:46 PM
#71
Ideally, it's just whatever the tires can handle at any instant so there will be some modulation (we call it testing) needed to stay right at the limit. It typically looks like a stairstep when someone gets good at it. There will also be some testing with the steering as well. Some drivers tend to test more with one or the other, some work both together more. You can find many videos of top drivers on youtube that shows throttle and steering to get the idea.
If you are working with someone newer in a track day type situation however, you probably want to suggest just doing a smooth throttle application unless you want them spinning on every other corner. It typically takes someone a good bit of training to get to the point where they are balancing the car on the edge of oversteer during exit.
If you are working with someone newer in a track day type situation however, you probably want to suggest just doing a smooth throttle application unless you want them spinning on every other corner. It typically takes someone a good bit of training to get to the point where they are balancing the car on the edge of oversteer during exit.
03-31-2018, 09:11 PM
#72
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Does anyone know if there is a video that has been filmed from the air to show this technique in slow motion?
Last edited by NYoutftr; 03-31-2018 at 09:30 PM.
03-31-2018, 09:36 PM
#73
We have a video showing this that's on youtube. I can't post a link directly, but it's during the part with the Lotus. It might be useful to watch but I wouldn't try to mimic the driver inputs. They have to be reactions and they will come naturally with practice if you continue to push your skills. Think about it like learning to walk a tightrope. You can probably learn some basic ideas by watching a pro do it, but really you just have to get up on the thing and start developing your balance. Using more forgiving street tires can be useful to ease someone into it though.
03-31-2018, 09:46 PM
#74
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Shouldn't need the latter unless the throttle app is too quick, abrupt or you're pinching the exit with continued steering input.
Adam's suggestion to open the steering as the throttle opening is increased is proven.
The classic "string from the bottom of the steering wheel to the top of the throttle pedal" relationship. Been a SBRS curriculum staple since 1975.
In the video provided by the OP, this is done extremely well by young Mr. Pank through and off of Turn 5. Almost perfectly.
The best driver's data shows a smooth (but NOT slow) progression to WOT. No steps, hesitations, modulations or, heaven forbid, retractions...
To quote 3-time Formula 1 world Champion, Sir Jackie Stewart:
“Don’t put your foot on the gas pedal until you’re sure that you’ll never have to take it off again.”
Adam's suggestion to open the steering as the throttle opening is increased is proven.
The classic "string from the bottom of the steering wheel to the top of the throttle pedal" relationship. Been a SBRS curriculum staple since 1975.
In the video provided by the OP, this is done extremely well by young Mr. Pank through and off of Turn 5. Almost perfectly.
The best driver's data shows a smooth (but NOT slow) progression to WOT. No steps, hesitations, modulations or, heaven forbid, retractions...
To quote 3-time Formula 1 world Champion, Sir Jackie Stewart:
“Don’t put your foot on the gas pedal until you’re sure that you’ll never have to take it off again.”
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-Peter Krause
www.peterkrause.net
www.gofasternow.com
"Combining the Art and Science of Driving Fast!"
Specializing in Professional, Private Driver Performance Evaluation and Optimization
Consultation Available Remotely and at VIRginia International Raceway
04-01-2018, 06:09 PM
#75
If you drive a fwd car as I do you will learn to rotate the car as a matter of course i.e. early in your experience. If you don't you'll take the term understeer to new heights, as well as spend all of your available disposable income on tires 
This also applies to throttle application as Peter alludes to above--too early, lift or cook the tires with u/s--too late, be slow. Just right, just right 
Gary
This also applies to throttle application as Peter alludes to above--too early, lift or cook the tires with u/s--too late, be slow. Just right, just right Gary