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-   -   Is Heal Toe braking necessary for modern cars on track days. (https://www.scoobynet.com/driving-dynamics-354/484903-is-heal-toe-braking-necessary-for-modern-cars-on-track-days.html)

GarySheehan 28 March 2006 04:31 PM

rmtypeR,

It's not really that fast. Once you learn to synchronize the steps of it, it doesn't take any longer than a normal, non-rushed downshift. The trick to the whole thing is that the gear lever doesn't really pause in neutral for any length of time. As I'm moving the shift lever out of gear, I'm already letting up on the clutch and beginning a throttle blip. Once I feel the lever hit neutral, I'm already starting to clutch in again and move the lever into the next lower gear.

So, for me, there aren't eight distinct seperate steps to the downshift as have been pointed out before (which are correct). It's more like my body doing three different activities simultaneously, all sychronized to work together. The three activities are (in no order, since they all happen together):

a. Right hand moves shift lever to neutral, then to next lower gear.
b. Left foot pumps clutch twice quickly
c. Right foot depresses brake and throws in a throttle blip at some point.

So, when you think about the body's ability to parallel process, it becomes a much simpler task of perfoming three activities simultaneously rather than performing eight seperate activities serially.

Watch the video again and look at it from the point of view of three parallel actions now, rather than how you watched it the first time. It should look a lot different.

Did that help?

Gary
Sheehan Motor Racing
www.teamSMR.com

JTaylor 28 March 2006 05:00 PM

Thanks for taking the time out to clarify some of the points on this thread Gary, it's good to get a professional's input.

rmtypeR 28 March 2006 05:35 PM

Yes, thanks Gary :thumb: I'm going to go out and practice this weekend, though I'll start with just heal & toeing then maybe try the double clutch when I've got the hang of that. My experience of double clutching comes from driving trucks designed in the 1950's where you pretty much had to do it to avoid crunching the gears - this is what made me think of it being a slow process.

Is it a common practice for race drivers to double declutch or is it more just something you like to do?

Edited to ask - What sort of spec is the car you're driving in the vid - it sounds great! And I recognise that track - I've driven it in Gran Turismo 4 :)

gazberwick 07 April 2006 03:24 PM

LOOK AT THIS MPEG
 
Have a look at this vid...pull the progress slider to about halfway an look for the inset camera on the drivers feet it shows you quite well what H+T is all about. ISH!!

http://videos.streetfire.net/search/...025D66A083.htm

CBM555 15 October 2006 10:10 PM

Now that`s the way to do it. especially if your on a track.

CBM555 15 October 2006 10:11 PM

Now that`s the way to do it. especially if your on a track.

RB5_245 17 October 2006 01:31 PM

Actually, you would never need to keep the car that settled under braking (assuming youre smooth on the clutch) as you should have your gear sorted before turning in. if you're changing down on approach to the apex you're going to hit it a gear too low and run out of revs on the exit - forcing a gear change whilst cornering under power.

Only time I would say H/Ting its an advantage in if your braking zone is on a sweeping corner tightening.

However I H/T all the time regardless, it's nice and smooth and I like it :D

I ddc the impreza into first regularly approaching junctions or near stopping situations. It just slots in perfectly, no fuss.

Dave

Kubaz 25 December 2006 08:32 AM

i think when you are shifting down quickly after you start braking you don't need to use this technique.

i tried it too but size of my feet is 12 so i can step on the clutch with my toe and on the gas pedal with my heel... 8)

zip929 25 December 2006 12:33 PM

Here is a good example
 
YouTube - NSX at Nurburgring

rabskyline 30 December 2006 04:13 PM

i heel and toe all the time. its just habit now ! i live out in the sticks and there are a load of cross roads and t junctions where it helps massively. no more pitching and rolling. it also helps on the loose ground as it stopd the clutch from snatching gears etc...a more fluid drive.

moneys 31 December 2006 01:22 AM

BTTT

superstring 31 December 2006 07:40 PM

Does anyone else find it difficult to accurately modulate the brake pedal pressure while blipping the throttle?

PS Happy New Year!

ex-webby 01 January 2007 08:46 PM

it can be tricky at first. But keep practicing, and it'll start to come naturally..
its also easier with softer shoes!

Dark Blue Mark 01 January 2007 08:50 PM

String, think about braking first and the throttle blip second. So focus all your attention on the ball of your foot part, while putting your heel down onto the throttle.

Nasty if you get it the wrong way round :D

MB

superstring 01 January 2007 10:09 PM

Yeah, thanks guys. I find it easiest when braking hard. That way the brake pedal provides a more stable platform to pivot your foot on. Really hard braking is not usually the way I brake around town, though ;)

As an aside, did you guys know that the term "heel and toe" came about when Ferrari built a race car with the brake and throttle pedals reversed, ie throttle in the middle and brake on the right, to facilitate the technique. So your heel would actually be used on the brake and toe on the throttle. As you might imagine, the car did not have a very successful career. I think it was Phil Hill who talked about forgetting which pedal was which in the heat of the action! :eek: :D

Dark Blue Mark 01 January 2007 11:10 PM

Round town its pretty pointless though, and more difficult as you say.

MB

GeeDee 29 January 2007 09:05 AM


Originally Posted by MY93WRX (Post 5374378)
I Do i try and use it or should i stick with my usual "cat'n'fiddle" (great road) / country lane method of initially braking hard down shifting through the gears then decreasing brake presure as i aproach the corner (Whilst applying the IAM technique of reading the road :wonder:

Since when has the IAM advocated shifting down through the gears? Surely, you select the right gear for the situation first time?

Also, when doing your downshifting whilst braking without heel and toe how do you synchronise the engine speed - or do you let the clutch do the work?

rasheedn 29 January 2007 05:07 PM

yeah
it really helps in the wet
if u dont use it u will probably lockup once a while or sth

ru' 29 January 2007 05:46 PM

Surely by heel and toeing you'd reduce the likelyhood of locking up as there would be no 'jerk' from releasing the clutch due to the revs being matched???

Dill_typeR 29 January 2007 06:17 PM

I've tried to do this but can't seem to angle my foot right, and it just slips off the brake pedal, need to learn tho as changing from 5th to 4th i get a crunch when caning it on track:cry:

GeeDee 30 January 2007 06:10 PM

One of the first things I do on getting a new car is to make sure the brake and accelerator are positioned correctly and safely for H+T.

You can normally bend the pedals relatively easily - but don't go overboard!

superstring 30 January 2007 07:15 PM


Originally Posted by gdavey (Post 6608236)
One of the first things I do on getting a new car is to make sure the brake and accelerator are positioned correctly and safely for H+T.

You can normally bend the pedals relatively easily - but don't go overboard!

On my car the brake pedal, when stepped on, ended up significantly lower the accelerator. As you can imagine this made H&T virtually impossible. I installed an OMP accessory pedal by drilling the original and making some spacers out of aluminum tubing. The OMP pedal sits atop the spacers about 12mm higher than before. Now, when I brake, the brake and accelerator are at the same height. :)

TimH 02 February 2007 06:01 PM

I'd been having problems with heel/toe on my MY05 JDM STi as the throttle needed quite a "deep" push to blip the revs. Problem sorted by tightening up the throttle cable to remove the excessive play before it actually did anything.

Cheapest mod I've ever made :D

SC008Y_MAD 02 February 2007 06:16 PM

I use this method. My dad tought me this when I was learing to drive, which my dad learnt it from a close friend. My dad said I was a natural and picked it up quicker then I/He did.
I can't heal and toe as there is no room in my sport, I can however do it in a new age as there is a lot more room.


Originally Posted by dazdavies (Post 5376099)
What about a simple double de-clutch? i.e brake, lift off break, clutch down and blip throttle , change down back on brake.

Once you get used to doing it works well. Also gives your gear box an easier time.


Del mar 07 March 2007 02:12 PM

Interesting reading.

Most Superbikes now come with "Slipper Clutches", so that when changing down the rear wheel does not lock up when you come off the clutch. I appreciate that their gearboxes are sequential, but would the same logic apply ?

Del


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