Heel-Toe Shifting
03-23-2009, 03:36 PM
#16
Rennlist Member
I've only done this in karts. explain to me what happens with left foot braking that cant be done with lifting. are you really concerned with keeping the gas on so that that there is no lag with when you do get on the gas, if you were left foot braking? or is it a balance of power thing, where the gas and the brake applied at the same time, basically creates less rear brake force bias.
I do like to do do it with karts, but the centrifugal clutchs work better when the engine is spinning faster, so you keep the thing floored and use the brakes which just over power the rear forces. I would think the shifter Karts do something similar, just to keep the power applied.
I dont left foot brake, but ive seen it done on Tv.
mk
I do like to do do it with karts, but the centrifugal clutchs work better when the engine is spinning faster, so you keep the thing floored and use the brakes which just over power the rear forces. I would think the shifter Karts do something similar, just to keep the power applied.
I dont left foot brake, but ive seen it done on Tv.
mk
03-23-2009, 04:16 PM
#18
Rennlist Member
I've only done this in karts. explain to me what happens with left foot braking that cant be done with lifting. are you really concerned with keeping the gas on so that that there is no lag with when you do get on the gas, if you were left foot braking? or is it a balance of power thing, where the gas and the brake applied at the same time, basically creates less rear brake force bias.
I do like to do do it with karts, but the centrifugal clutchs work better when the engine is spinning faster, so you keep the thing floored and use the brakes which just over power the rear forces. I would think the shifter Karts do something similar, just to keep the power applied.
I dont left foot brake, but ive seen it done on Tv.
mk
I do like to do do it with karts, but the centrifugal clutchs work better when the engine is spinning faster, so you keep the thing floored and use the brakes which just over power the rear forces. I would think the shifter Karts do something similar, just to keep the power applied.
I dont left foot brake, but ive seen it done on Tv.
mk
Mark, lifting raises the rear of the car unnecessarily, whereas LFB merely adds bite to the front and aids rotation, while allowing you to remain on the gas to keep the rear planted. Think about turns at Laguna that do not require a downshift (for many cars, this would be 3 and 9, for example). Lifting there & hitting the brake would not be as productive as remaining on (at least some) throttle and LFB.
Some cars, such as 2001+ 911's with eGas, will cut off the gas if you LFB, hindering its usefulness. However, you can still use it by not pushing the brake pedal very much (tricking the system).
Professional Racing and Driving Coach
03-23-2009, 04:48 PM
#19
Mr. Excitement
Rennlist Member
Rennlist Member
also... Lifting causes only the rear wheels to slow the car where as LFB uses the front more as most cars have more front brake bias. Faster on and off times than the motor spooling up and down and more exact too.
Learn it on the street as you left leg is more in tune with mashing a clutch. Real suprise when it does the same to the brake when called into service.
I like the term left foot balance. Far more discriptive of real use.
Learn it on the street as you left leg is more in tune with mashing a clutch. Real suprise when it does the same to the brake when called into service.
I like the term left foot balance. Far more discriptive of real use.
03-23-2009, 05:13 PM
#20
Rennlist Member
I can certainly see tricking the bias setting, but doesnt any deceleraton create weight transfer? (whether rear or front brake initiated)
I guess there are two kinds of thoughts here. at laguna, as VR has mentinoed. I love to see brake lights out of turn9. it means the guy in front is not confident in the grip, as it is a little bit of a daunting sweeper. however, his point is that i wouldnt have to lift as much which does lift the rear end up, ill admit, and it might stay more planted if i do the same LFB that creates the same amount of decel as Im used to by lifting? If that is the case, am i not counter acting the rear brake bias by doing so and just applying more braking force in front as little as it is, on the slight decel around turn 9 at laguna ?( exit of the corkscrew down hill left for those not familar with this turn.)
Also, there are turns like turn 8 at Thunderhill that could be a nice candidate for testing this out. currently, its a lift and quick stab of the brakes from 120mph to 100mph. left foot braking could allow less rear braking force on the approach.
VR also mentioned turn 3 at laguna. Its a pretty dramatic stab, threshold brake. pretty traditional, as I dont think that would be a likely candidate for LHB, but turn 4 might be as it is much faster and a much quicker stab of the brakes.
I know what you mean about knee jerk reaction of the left foot. I do a lot of left foot braking when bedding my brake pads and the foot feels pretty nimble. Ill do some left foot braking turns on the way to the track this weekend to practice. I think turn 10 at sears might be a nice candidate, but dangerous!!
mk
I guess there are two kinds of thoughts here. at laguna, as VR has mentinoed. I love to see brake lights out of turn9. it means the guy in front is not confident in the grip, as it is a little bit of a daunting sweeper. however, his point is that i wouldnt have to lift as much which does lift the rear end up, ill admit, and it might stay more planted if i do the same LFB that creates the same amount of decel as Im used to by lifting? If that is the case, am i not counter acting the rear brake bias by doing so and just applying more braking force in front as little as it is, on the slight decel around turn 9 at laguna ?( exit of the corkscrew down hill left for those not familar with this turn.)
Also, there are turns like turn 8 at Thunderhill that could be a nice candidate for testing this out. currently, its a lift and quick stab of the brakes from 120mph to 100mph. left foot braking could allow less rear braking force on the approach.
VR also mentioned turn 3 at laguna. Its a pretty dramatic stab, threshold brake. pretty traditional, as I dont think that would be a likely candidate for LHB, but turn 4 might be as it is much faster and a much quicker stab of the brakes.
I know what you mean about knee jerk reaction of the left foot. I do a lot of left foot braking when bedding my brake pads and the foot feels pretty nimble. Ill do some left foot braking turns on the way to the track this weekend to practice. I think turn 10 at sears might be a nice candidate, but dangerous!!
mk
also... Lifting causes only the rear wheels to slow the car where as LFB uses the front more as most cars have more front brake bias. Faster on and off times than the motor spooling up and down and more exact too.
Learn it on the street as you left leg is more in tune with mashing a clutch. Real suprise when it does the same to the brake when called into service.
I like the term left foot balance. Far more discriptive of real use.
Learn it on the street as you left leg is more in tune with mashing a clutch. Real suprise when it does the same to the brake when called into service.
I like the term left foot balance. Far more discriptive of real use.
03-23-2009, 05:30 PM
#22
Race Director
LFB is a nice tool to have in your bag of tricks. Certainly not every turn will be faster with it. Depeding on the track and the car I would expect it to be no faster or a nice edge faster than a standard right foot braker.
03-23-2009, 08:45 PM
#25
Rennlist Member
03-23-2009, 08:53 PM
#26
Rennlist Member
Got it. So, how is it different to lift and brake slightly or LFB into 4 for example.
weight transfer is the same if you need to slow to the same speed before turn'in. the only difference I can see is that you have now slightly neutralized your braking bias toward the front wheels, vs using lift and brake. Is it the smoother transision that could be the advantage, certainly , your overall braking is less, so it might also force you to brake earlier, which in itself could help or hurt. How much of it is being able to get on the throttle and have power and fuel flow earlier? I dont know about you, but in the apex of the turns, I cant hammer the throttle anyway so I dont know if that is an advantage.
One other thing,is that if the rear end geometry is set up for squat under rear breaking, this lowering of the CG wouldnt happen as much either.
Ill have to see if I can see any benifits of it this weekend if I have the guts to try it. usually, at Sears you have your hands full with survival anyway!
mk
weight transfer is the same if you need to slow to the same speed before turn'in. the only difference I can see is that you have now slightly neutralized your braking bias toward the front wheels, vs using lift and brake. Is it the smoother transision that could be the advantage, certainly , your overall braking is less, so it might also force you to brake earlier, which in itself could help or hurt. How much of it is being able to get on the throttle and have power and fuel flow earlier? I dont know about you, but in the apex of the turns, I cant hammer the throttle anyway so I dont know if that is an advantage.
One other thing,is that if the rear end geometry is set up for squat under rear breaking, this lowering of the CG wouldnt happen as much either.
Ill have to see if I can see any benifits of it this weekend if I have the guts to try it. usually, at Sears you have your hands full with survival anyway!
mk
03-23-2009, 09:34 PM
#27
Burning Brakes
Thread Starter
Eddie,
I used to lfb at T10, but that is one place I do not want to loose it, so I brake normally and trail brake through turn-in. I'm going a little faster at the top of the esses than I used to. No lfb in T17. I am back on the gas before the first inside (right side) gator and WOT shortly therafter. Might be woth a try though. I did spin there in Feb.
I used to lfb at T10, but that is one place I do not want to loose it, so I brake normally and trail brake through turn-in. I'm going a little faster at the top of the esses than I used to. No lfb in T17. I am back on the gas before the first inside (right side) gator and WOT shortly therafter. Might be woth a try though. I did spin there in Feb.
03-23-2009, 09:53 PM
#28
Burning Brakes
Thread Starter
Coryf, Finally watched your video. Excellent footwork. Reminds me of something I do not do often enough, especially with brakes about the same size as those on a Schwinn: left foot making sure you have brakes in the middle of a straight. I need to make that an every-lap practice.
03-23-2009, 10:11 PM
#30
Rennlist Member
Got it. So, how is it different to lift and brake slightly or LFB into 4 for example.
weight transfer is the same if you need to slow to the same speed before turn'in. the only difference I can see is that you have now slightly neutralized your braking bias toward the front wheels, vs using lift and brake. Is it the smoother transision that could be the advantage, certainly , your overall braking is less, so it might also force you to brake earlier, which in itself could help or hurt. How much of it is being able to get on the throttle and have power and fuel flow earlier? I dont know about you, but in the apex of the turns, I cant hammer the throttle anyway so I dont know if that is an advantage.
One other thing,is that if the rear end geometry is set up for squat under rear breaking, this lowering of the CG wouldnt happen as much either.
Ill have to see if I can see any benifits of it this weekend if I have the guts to try it. usually, at Sears you have your hands full with survival anyway!
mk
weight transfer is the same if you need to slow to the same speed before turn'in. the only difference I can see is that you have now slightly neutralized your braking bias toward the front wheels, vs using lift and brake. Is it the smoother transision that could be the advantage, certainly , your overall braking is less, so it might also force you to brake earlier, which in itself could help or hurt. How much of it is being able to get on the throttle and have power and fuel flow earlier? I dont know about you, but in the apex of the turns, I cant hammer the throttle anyway so I dont know if that is an advantage.
One other thing,is that if the rear end geometry is set up for squat under rear breaking, this lowering of the CG wouldnt happen as much either.
Ill have to see if I can see any benifits of it this weekend if I have the guts to try it. usually, at Sears you have your hands full with survival anyway!
mk
But the weight transfer is not the same. See my earlier post for why. And you don't need/want to hammer the throttle. But LFB in places like this (assuming no gear change) allows more throttle thru midcorner, and thus more speed carried to the point where you actually can go to WOT. If you can carry even 10% more gas thru the entirety of the corner, that is an advantage.
Professional Racing and Driving Coach