I do it more for the smoothness factor than anything else. I'll occasionally pull one around a corner to get more exit speed, but not often.
Oh well. All cleared up for me anyway. I'll still keep doing it.
How do you heel-and-toe?? noob question
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Okibi
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Blipping the throttle on down shift.
(I know these figures aren't accurate)
Say your car does 50km/h in 4th gear at 3000 rpm
and your car does 50km/h in 3rd gear at 5000 rpm
and your car does 30km/h in 3rd gear at 3000 rpm
If you were to change down without blipping the throttle from 4th at 3000rpm to 3rd (still at 3000 rpm) you car would suddenly lurch as the gearing would try and slow it to 30km h.
The driveline would also take extra pressure as it tries to slow your car down 20 km/h.
Using the above table..
If you were to change down WITH \"heal toe\" blipping the throttle from 4th at 3000rpm to 3rd, you would take the car out of gear, blip your throttle so that the engine revs climbed to 5000 rpm then change into 3rd and keep going at 50km/h.
This way the car would only loose power for a second and remain as balanced as possible.
I hope that was clear enough for some of the users of the forum who may still be confused.
I use \"heal toe\" down shifting everyday, even in mums bunky 121.
Double De Clutching is used to get that next gear spinning in the gear box to reduce the wear on it when you change into that gear.
(I know these figures aren't accurate)
Say your car does 50km/h in 4th gear at 3000 rpm
and your car does 50km/h in 3rd gear at 5000 rpm
and your car does 30km/h in 3rd gear at 3000 rpm
If you were to change down without blipping the throttle from 4th at 3000rpm to 3rd (still at 3000 rpm) you car would suddenly lurch as the gearing would try and slow it to 30km h.
The driveline would also take extra pressure as it tries to slow your car down 20 km/h.
Using the above table..
If you were to change down WITH \"heal toe\" blipping the throttle from 4th at 3000rpm to 3rd, you would take the car out of gear, blip your throttle so that the engine revs climbed to 5000 rpm then change into 3rd and keep going at 50km/h.
This way the car would only loose power for a second and remain as balanced as possible.
I hope that was clear enough for some of the users of the forum who may still be confused.
I use \"heal toe\" down shifting everyday, even in mums bunky 121.
Double De Clutching is used to get that next gear spinning in the gear box to reduce the wear on it when you change into that gear.
If you had access to a car like this, would you take it back right away? Neither would I.
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Boags
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Re:
Okibi wrote:YES! toe on brake, heel (or side of foot) on the accelerator.
It doesn't matter so much if your foot slips off or misses the accelerator but you must have full control of the brake.
My Datsun race car has a crap accelerator pedal, so I have to heel the brake and toe the accelerator up the top of the pedal...
Bloody datsuns...
Boags
Spartan Motor Sport : http://www.SpartanMS.com.au
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Boags
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Re:
marcusus wrote:Serves you right for having a datto
Touche'Spartan Motor Sport : http://www.SpartanMS.com.au
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Okibi
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Benny
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In case you didn't know, your synchros work with friction.
They actually try to match the speed of the input and output shafts of your gearbox when you change gears.
Obviously, anything that works on friction will wear out eventually, and DD/C'ing will lessen the wear on your synchro rings, if you DD/C properly.
You don't have to do it, just like you don't have to stop smoothly, but it does make for smoother driving, and less wear and tear on your synchros.
Not only that, but DD/C'ing on down changes will also make the changes FASTER (and smoother) than pushing against the synchros and waiting for them to mach the speeds of the input and output shafts, as you are doing their work for them, and the engine revs quicker than the synchros can.
I used to have to use my heel on accelerator and toe on the throttle when H&T'ing, but that was only in an old Holden I once had where the brake and the throttle were miles apart from each other.
Otherwise, it's toe on the brake and side of the foot on the throttle.
They actually try to match the speed of the input and output shafts of your gearbox when you change gears.
Obviously, anything that works on friction will wear out eventually, and DD/C'ing will lessen the wear on your synchro rings, if you DD/C properly.
You don't have to do it, just like you don't have to stop smoothly, but it does make for smoother driving, and less wear and tear on your synchros.
Not only that, but DD/C'ing on down changes will also make the changes FASTER (and smoother) than pushing against the synchros and waiting for them to mach the speeds of the input and output shafts, as you are doing their work for them, and the engine revs quicker than the synchros can.
I used to have to use my heel on accelerator and toe on the throttle when H&T'ing, but that was only in an old Holden I once had where the brake and the throttle were miles apart from each other.
Otherwise, it's toe on the brake and side of the foot on the throttle.
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