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-   -   Heel & Toeing (https://www.scoobynet.com/driving-dynamics-354/314866-heel-and-toeing.html)

garetgax 24 May 2004 06:22 PM

left foot breaking
 
Tried left foot breaking in my Fto before the scooby .Nearly went through the windscreen . Havent treid it since. What are the benifits in the wrx for this and heel and toe? Also have an MR2 would it help for that?

ScoobySport (SdB) 24 May 2004 07:24 PM

Good subject this...

The important thing is to first decide why you're doing it / what it's for, rather than trying the technique, then trying to work out what use it is :D

Heel & Toe :
When braking long and hard you transfer load from the rear of the car to the front. This means that the front tyres are gripping a lot more than they usually do, and the rears are gripping a lot less than they usually do. This effectively means the car is a potential tail happy beast.

Due to the laws of the traction circle, any longitudinal demand you place on the tyres (as with sudden engine braking) removes some of the tyre's ability to grip laterally (to stop you spinning).

So the purpose of the heel and toe is to reduce or potentially eliminate sudden engine braking due to downshifting by bringing the revs up to match the gear you're selecting.

This means that the ideal time to blip the throttle is just enough time to allow the revs to build to the desired level prior to you releasing the clutch in the new gear.

Left Foot Braking :
This is a more complex one, but generally in performance / competition driving terms, left foot braking is to aid in turning the car and balance / adjustment mid bend.

It's obviously not quite this simple, but generally speaking, more left foot = more grip on the front tyres / more oversteer / more turn-in.

Why is it necessary?

If you ignore left foot braking, you only really have two methods of loading up the front tyres (in order to create more bite in the front end).. a) lift off, b) come off the gas, and press the brake.

lifting off alone is great, but it only has a very limited and less accurate effect.
coming off the gas and hitting the brake is great, but takes a whole load of time and the turbo dies

so the ideal solution is use left foot braking so you can squeeze the brakes as and when you like as hard as you like and as quickly as you like whilst maintaining full boost and instant response.

--

As a side note (much less important, but worth a mention), it can also be very helpful during big jumps. It is actually possible to control the car whilst in mid-air. Hitting the brakes mid flight will dip the nose, hitting the gas will (to a much lesser extent) lift the nose.. all of this helps you control your landing a lot more accurately and help prevent the dreaded back-flip! :D

All the best

Simon

New To Scoob 25 May 2004 09:01 AM

Heel & Toe, learnt it a while ago with my Mk2 Escort, only problem is now it seems more of a habit than anything else, feels like it gives me more control coming into corners.
Left Foot Braking, took ages to learn this, as with most I just about cut myself in half with the seatbelt the first time I tried it, now I've got more used to it, the 03STi seems to suit me for left foot work, comes in ready handy on long sweepers allowing me to keep a better line and keep the engine on song for the exit, the Mrs still wonders what I'm up to at times though :D

John.

FrenchBoy 25 May 2004 07:02 PM

I found learning to left fook brake in a **** car (ford 1.3 orion) a neccesity due to the fact that the car would stall when stationary.

so in order to keep it ticking over when approaching a junction/lights/traffic etc i had to
1) put it in neutral while still moving
2) Hold at least 1k revs with my right foot
3) brake with my left foot and bring the car to a standstill (while still holding 1k revs)

very annoying but ultimately rewarding!! :)

(what is it they say about neccesity being the mother of invention?)

ScoobySport (SdB) 26 May 2004 10:24 AM

LOL :D

OK.. just to be clear here.. there should never be any need (other than emergency) to bring the car to a stop using left foot braking. Indeed, actual slowing down of the car for slowing down sake is rarely done with left foot braking, unless a) you have a sequenctial box / dog box capable of clutchless gear changing, or b) you don't intend to change gear anyway.

To give an example, let's take a situation where you're in 5th gear (or 6th if you're a show-off! ;)) and approaching a 3rd gear bend.

Start braking normally with your right foot using heel and toe if desired until you get into third gear (which is likely to be sometime around the point you start your turn-in, but not necessarily) and making sure you're only using the right hand side of the brake pedal (don't try this at home, practice in safe place, etc, etc)... at this point move your left foot to cover the left hand side of the brake pendal and smoothly (this bit requires practice) take up the pressure with your left foot so you can remove your right foot from the brake pedal and move it to the gas pedal.

The more tricky part is where you then left foot brake through the 3rd gear bend approaching a second gear section.. which means you need to swap back to right foot braking (by reversing the above technique) to free up your left foot for the clutch, and then swap back again for left foot braking through the second gear bend.

It's really tricky to get sorted, but after lots of practice it become second nature.

I personally (although this is not advice in any way) think that mastering this technique makes you a safer driver on the road as it gives you a) lots more options of control and b) provides a far quicker reaction time to get on the brakes in an emergency. But there is no question that not being able to do it well, and still trying to can be very dangerous.

All the best

Simon

EddScott 26 May 2004 01:08 PM

I've got size 11s and use the inner ball outer ball to blip the throttle on downshift. I use it quite alot where neccessary to be as gentle as possible on the transmission and clutch - also get quite a nice "Pop" too on occasion :)

What about going up the box though? would you blip the throttle going up to prevent the jerk of a higher gear lower revs? If I'm not pressing on I tend to build up the revs but allow the boost to tail off before changing to lessen the jerk of WOT- change -WOT - nack'd 'box.

ScoobySport (SdB) 26 May 2004 02:44 PM

No need to blip on up-shift, as you actually want the revs to drop rather than increase.

cheers

Simon

TopBanana 26 May 2004 02:51 PM

BTW, I don't recommend left-foot braking any VAG turbocharged cars - all the boost is instantly lost after a second or two of covering the brake :rolleyes:

ScoobySport (SdB) 26 May 2004 04:03 PM

That's a very good point actually jlanng which I forgot to mention.

I've been driving a GTi turbo deisel golf while my scooby was off the road and it's been a killer training myself not to left foot brake.

TopBanana 26 May 2004 06:38 PM

Annoying isn't it!

Spooks 26 May 2004 08:08 PM

Wish I could do heal toe more but alas only got wee feet and I can hardly reach the throttle pedal :( and maintain the preasure on the brakes. its bloody hard work I can tell ya....gotta say when ya do get it all right then its great.
Left foot braking is good if your wanting to get the car set up on the brakes without loosing boost, basically if your getting thrown through the window thats cause your doing it wrong.....you shouldnt have any servo assistance if your doing it right so unless you jump like feck on the pedal its hard to be thrown like that, at least thats what I was told.
Now disclaimer time Im a cack driver so if im wrong this is the reason why LOL ;)
Spooks

DuncanG 26 May 2004 10:19 PM


Originally Posted by Spooks
.....you shouldnt have any servo assistance if your doing it right so unless you jump like feck on the pedal its hard to be thrown like that, at least thats what I was told.

Not quite right.
The servo has a chamber that stores vacuum which is created whenever the throttle is closed. So the 1st and maybe 2nd or 3rd application of left foot brake (assuming still on throttle), after overrun for example, will have vacuum assistance until the vacuum is depleted. The varying level of assistance can catch you out!

ScoobySport (SdB) 28 May 2004 10:30 AM

Agreed Duncan

In addition, this is rarely a problem as you almost always come off the gas at some point during the bend / while braking.

It is true though that you *can* get caught out.

All the best

Simon

David_Wallis 10 June 2004 09:23 PM

Its fooking annoying when you realise if your pressing on its second nature to heel and toe, however what is annoying when your in a diesel and you try doing it..

Brake pedal needs no encouragement for the nose to dive so I have to be gentle.. but accelerator pedal needs two - three inches of pressing..

Makes for entertaining entrances to roundabouts.... Must stop trying.. <argh>

However 4 ****e quality tyres make for low speed - (30 -40 mph) four wheel drift entertaining.. The lack of throttle control doesnt though.. Must give up being a dick in a mondeo...

Now wheres the spare boost gauge and where is that actuator rod..

David

craigdmcd 21 June 2004 11:05 PM

The man is mostly right
 
The man with the title Scoobysport is giving you the most sensible advice on here gents, but so I get my own tuppence in, no healing and toeing should ever be used on an upshift, it's not necessary and it's not needed, just a superfast shift is required to give as little engine speed drop as possible (try pulling the gear lever out of its current gear as you just starting to press the clutch, but be sure that the clutch is down by the time you have slotted across the neutral of the gate and sliding it in to your next gear up). Healing and toeing for downshifts is the main topic here and the man has mostly explained it very well with the excepetion that when you blip, you are increasing the revs so the syncros in the gearbox get a better chance to match the speeds of the two gears so as not to cause to many inertial forces with the braking etc.

Left foot braking seems to be giving you the biggest runaround. This style of driving has two main advantages, and only one of them is any use on on most normal driving or even on track days unless you are just wanting to show off and put in slow lap times. The first ( and mostly unusable) is when in a competition/rally car and heading to a loose corner, with a brake bias set more to the rear than the front, you would use left foot braking to unsettle the car on the entry to the corner so that you have already started getting the car nearer to your desired exit angle whilst sliding through the corner.
Nice but not quick on the road or track. The second is to assist on long corners to help keep the nose of the car down by gentle application so as to give as much acceleration as possible without understeering straight off the corner as the front wheels go light and give no lateral (turning) help.

All techniques require practice, and some people should not even try some mentioned here.

P.S Here's my disclaimer: if you don't know how to do them already, your probably not going to manage it easily, and it's far easier to drive up to your own limits than match somebody else!!!!:D :D :D

greasemonkey 22 June 2004 12:41 AM


Originally Posted by DuncanG
Not quite right.
The servo has a chamber that stores vacuum which is created whenever the throttle is closed. So the 1st and maybe 2nd or 3rd application of left foot brake (assuming still on throttle), after overrun for example, will have vacuum assistance until the vacuum is depleted. The varying level of assistance can catch you out!

I've removed the servo completely on the last couple of roadcars I've had. Partially because they've both got ALS, but notwithstanding that I find the totally consistent and feedback rich brake pedal far more rewarding to drive quickly with.

New To Scoob 22 June 2004 08:18 AM


The more tricky part is where you then left foot brake through the 3rd gear bend approaching a second gear section.. which means you need to swap back to right foot braking (by reversing the above technique) to free up your left foot for the clutch, and then swap back again for left foot braking through the second gear bend.
Veerrryyy tricky more like, or it is for me anyway :rolleyes: but it is fun learning :D

John.

Paul_M 22 June 2004 09:04 AM


Originally Posted by David_Wallis
Its fooking annoying when you realise if your pressing on its second nature to heel and toe, however what is annoying when your in a diesel and you try doing it..

Brake pedal needs no encouragement for the nose to dive so I have to be gentle.. but accelerator pedal needs two - three inches of pressing..

Makes for entertaining entrances to roundabouts.... Must stop trying.. <argh>

However 4 ****e quality tyres make for low speed - (30 -40 mph) four wheel drift entertaining.. The lack of throttle control doesnt though.. Must give up being a dick in a mondeo...

Now wheres the spare boost gauge and where is that actuator rod..

David

LOL... was thinking the exact same thing reading the first few paragraphs about when I drove a company Mondeo TD a few years back (horrible old mechanical injection thing with 82 BHP :eek: not the new TDCi) then I realised you're talking about the same car!

Beside the huge travel needed on the accelerator compared to the brake, the worst thing I found was that giving the accelerator a blip produced absolutely no response from the engine, you had to actually hold your foot on the accelerator while braking to give the engine a few minutes to respond and slowly raise its speed.

That was the most unresponsive engine I've ever driven, unbelievable turbo lag as well - they must have used a TD06 with a 2mm inlet housing so you get all the lag yet still only produce 0.1bar boost :D ;)

David_Wallis 22 June 2004 10:45 AM

Paul.. finaly someone that agrees... its called toe and floor it in my car!

was yours very laggy until 3k ??

then 3 - 4 ish wasnt too bad?

David

Damoleggy 30 June 2004 07:57 PM


Originally Posted by Graz
It's easier if you don't have a clutch to worry about ;)

Exactly, that is the best way of learning to left foot brake borrow someones auto and only brake left footed, when you get back into your manual it's easy. As for STI pedals any extension will do go and look at raldes.co.uk or demon tweeks sites and there are numrous pedal extensions which will do the job and probably for less dosh too. I have found that the bigger the extension on the throttle the better they are to heel & toe with.

Either way it looks cool as f$%K whe n you have passengers in the car and you pull it off at speed! :D :D

scrappydoo 01 July 2004 02:28 AM

When heal and toe-ing and you are changing down from 6th gear say into 3rd, make sure you get the gear change right as you just might get the wrong gear (5th) and thus be carrying to much speed for a corner and end up in a hedge. The trick is to get it into gear then balance the throttle asap round the corner till you apex, then start to accelerate out of it. It helps with flat shoes on as you can feel the pedals better.

Also with left foot braking, it is easier in an auto, thats where i taught myself. Piece of cake now in my Evo

J4MES 02 July 2004 11:44 PM

Craigdmcd was spot on with the left foot braking thing. To me, left foot braking is the technique the Scandinavians invented for getting a FWD car to turn in on the loose. Anything else is just braking with the left foot. A subtle difference.

It is something I have tried, unsuccesfully, to master over teh past few years whilst out on the stages. But I will persevere. I do tnd to use my left foot on the brake whilst in a long sweeper to settle the car. Or over a crest where I am unsure of the direction of the road (I don't trust my Dad on the maps!).

Now, who's for left foot braking and heel and toeing whilst throwing the car into a Scandinavian flick? :D

I think left foot braking and scandinavian flicks can only be fully exploited on loose surfaces. LFB, thats left foot braking and not Leopards Fanny Batter, can be adapted slightly for the black stuff.

My battered 205 is the guinea pig for my practice with the above techniques. Did you know they fitted Pug 205 1.1 Trio's with dog 'boxes? ;)

ScoobySport (SdB) 04 July 2004 04:27 PM

J4MES

LFB is of genuine use in FWD, 4WD and RWD cars on all surfaces. Itīs just a means of control.

All the best

Simon

pmacFTO 11 August 2004 09:28 PM

If you want to see some good heel-toe braking get the Best Motoring videos or VCD (or d/l them from WinMX or file sharing progs!) They show great races and close ups of the heel toe driving...it's impressive to watch.

http://www.standardshift.com/videos.html has a link to Heel Toe vid

http://www.teamsmr.com/movies/Footbox%20Small.wmv

RB5_245 12 August 2004 01:30 AM

IMHO the best motoring 'crew' don't always drive to the best of the cars abilities, just get the ar** out for good viewing.

Undoubtedly good car control but the peddle work is not so difficult with a bit of practise.

Dave

DuncanG 12 August 2004 09:34 AM

Footbox video -

Downchanging from 5th to 2nd = 3 double declutched shifts - hmm.
Assuming its a dog-box and he needs to double declutch can't you block-shift (ie go straight from 5 -2) with a dog-box?

KennyMck 19 August 2004 03:04 AM

I have size fifteen feet and use my right foot to operate all three pedals, with my left i change station on the radio or if not required for that task, i steer with it and change gear, this frees up my hands to light my pipe or adjust the rake of my trilby.

Droidy 19 September 2004 06:38 PM


Originally Posted by Steve001
arrh heal & toe :D

got it down to a fine art now even on my little nova rally car ;)

trouble is, all that blipping im sure my mpg is worse :D;)

next is mastering the dreaded LEFT FOOT BRAKING, now thats gonna take a bit more time :(

Give it a go if you aint already (make sure your seatbelt is secure on your 1st time) :D

I remember last year on the WRC rally coverage (Eurosport i think) they had a great shot of Petter's feet while on stage.... Talk about 'dancing' on the peddles :eek:

Have fun :D Steve

I did watch that, but then he did used to be a dancer
Jay

RB5_245 20 September 2004 12:50 PM


Originally Posted by DuncanG
Footbox video -

Downchanging from 5th to 2nd = 3 double declutched shifts - hmm.
Assuming its a dog-box and he needs to double declutch can't you block-shift (ie go straight from 5 -2) with a dog-box?

If you were to block shift from 5th to 2nd, when you shifted down from 5th the engine would be at very low revs where it's least responsive and make a smooth shift more difficult, also that minimises engine braking. The better option would be to make 3 shifts, which would be second nature to these folk.

Personally I've never felt the need to blockshift on the track or when pushing on. The only example I could think of is if you were braking through a sweeping corner, into a tighter corner where you don't want to take a hand off the wheel. I've only ever come across this on the road where I'd either take the tight corner a gear higher than normal or enter the sweeper at a slower pace. No point in getting the car out of shape on the road imo :)

Dave

mista weava 22 September 2004 02:59 PM

i taught myself left foot braking in an automatic vauxhall omega. if you are really wanting to hustle this vehicle on b-roads then it is an essential technique due to the gearing of this rather hefty car. its the only way to keep it on the boil.

i have used the techniques described in daily driving in the scoob. i have found that LFBing into a bend to be useful if its a sweeper as described above and the nose requires some settling. other tighter bends don't really lend themselves to this technique, you certainly will not take the bend sharper (on a sealed surface".

it is also especially useful as a boost building technique when you wish to overtake a vehicle on a short straight, or for holding the car back upon approach to a car you are about to overtake whilst waiting for a vehicle in the opposite direction to pass - ie: you sort of hover momentarily.

other than that its up to you and how you feel it befits your driving style. i think in auto cars its a must, in powerful manual vehilces it has its uses.


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