LEFT FOOT BRAKING...SLIP DIFF?

[C.slicker]

Just trying to settle and arguement with a friend...

Left foot braking is more or less useful in a car with an LSD?

Thanks

Sam

 

[Russ_16v]

cant see the difference between with or without mate i suppose with an lsd it might make the car a bit more stable as your left foot isnt accustomed to braking but apart from that i cant see a difference

 

[Josh@Renparts]

its not really directly related is it... doesn't it just keep the nose end down to keep the front end gripping?

 

[H5 D*P]

http://www.youtube.com/watch?v=jvNYFbJIJ-Y

 

[almaghrbi]

Just trying to settle and arguement with a friend...

Left foot braking is more or less useful in a car with an LSD?

Thanks

Sam

It is useful irrespective of whether you have LSD or not! It is the ability to switch between pedals and affecting the balance of the car

 

[C.slicker]

I was arguing its less useful in a car with LSD as the whole point is to stop the outside wheel spinning too quick which LSD does anyway?

 

[MarkCup]

Just trying to settle and arguement with a friend...

Left foot braking is more or less useful in a car with an LSD?

Thanks

Sam

Left-foot braking has many uses, not just on LSD equipped FWD cars either.

If gaining traction out of tight corners in low gears is your aim/debate, then the video above explains how it helps.

Unless I'm changing gear and need the clutch, I brake with my left foot. It can help to settle things mid corner or bring back a wayward front end. Speeds up/overlaps the brake to throttle transition as well which can help keep things smooth and balanced.

 

[C.slicker]

Right so you think I am talking b****cks about the LSD thing and it makes no difference?

On a side note:

With left foot braking, especially on cars such as petrol clios (i.e. not turbo so nothing down low in the rev range) is it not slower as you can't select the right gear?

E.g:

You are in say a 172 and you are going into a corner which your apex speed would be say 20. On the approach you might be approaching at 55, so you would be in 2nd. You then brake with your left foot to 20 for the apex but then you would be stuck in 2nd at 20 which is no good to anybody? So you would need to rearrange your feet losing valuable time?

:S:S:S

 

[Ex-User (19928)]

I can't think of a corner other than a u-turn at which you have to do 20 mate, but I know what you're getting at.

Once you've shifted down you can move your left foot over to the brake, it just allows you control to modulate both pedals compared to using your right foot placed over both pedals.

 

[Russ_16v]

I prefere heel and toeing to left foot braking,but its whatever you get along best with really

 

[Hollister]

I prefere heel and toeing to left foot braking,but its whatever you get along best with really

Apples and Oranges, two different techniques for two different things.

Leftfoot braking is for changing the balance of the car through corners (eg for correcting understeet).

Heel and Toeing is for matching engine revs with the gearbox when changing down, and unless you are using straight cut gears it isnt going to make much difference

 

[Fred@BTM]

ah ha, but heal and toeing keeps the car more stable under braking

 

[MarkCup]

I prefere heel and toeing to left foot braking,but its whatever you get along best with really

Apples and Oranges, two different techniques for two different things.

Leftfoot braking is for changing the balance of the car through corners (eg for correcting understeet).

Heel and Toeing is for matching engine revs with the gearbox when changing down, and unless you are using straight cut gears it isnt going to make much difference

I'm confused. How do straight cut gears (or lack of) render H&T changes redundant?

Can someone say if my 172 Cup has straight cut gears?

 

[Russ_16v]

no cars come with 'proper' straight cut gears,although from memory,old shape mini's 1st gears are straight cut...

you dont need to brake to correct understeer,just comiong off the power is enough usually,although i know whazt you mean mate

 

[MarkCup]

Ah ha...but by left foot braking you do not need to come off the power to correct understeer.

You can just shift a little weight forward mid corner while still keeping the momentum/speed building.

Which therefore makes it quicker.

 

[Russ_16v]

correct that man! its all about being smooth and keeping momentum up,that makes for a fast lap,inidentally iv been watching ur vids mark,boy u can drive!

 

[dan.clio]

Mark Cup is a legend ..... i was greatly impressed with his driving skills at the recent Cliosport Track Meet.

Awesome to watch!

 

[Hollister]

Apples and Oranges, two different techniques for two different things.

Leftfoot braking is for changing the balance of the car through corners (eg for correcting understeet).

Heel and Toeing is for matching engine revs with the gearbox when changing down, and unless you are using straight cut gears it isnt going to make much difference

I'm confused. How do straight cut gears (or lack of) render H&T changes redundant?

Can someone say if my 172 Cup has straight cut gears?

Straight cut gears require you blip the throttle to bring engine speed up to gearbox speed for the gears to mesh.

Helix cut gears as found on road cars use a syncromesh, which does the same job for you, so no use in heel and toeing

(ish, im not very good at explainations)

 

[jbCUP]

Heel and toe will help your syncros last a tad longer. Will also make your downshifts WAY smoother, and quicker which is handy when you're just about to reach a corner and wanna be on the power as you turn in...

 

[MarkCup]

I'm confused. How do straight cut gears (or lack of) render H&T changes redundant?

Can someone say if my 172 Cup has straight cut gears?

Straight cut gears require you blip the throttle to bring engine speed up to gearbox speed for the gears to mesh.

Helix cut gears as found on road cars use a syncromesh, which does the same job for you, so no use in heel and toeing

(ish, im not very good at explainations)

You're talking about double de-clutching aren't you, not heel and toeing?

Double de-clutching helps the gears engage by bringing input/output shaft rotation to the same speed so gears engage without a crunch. Modern cars do not need this technique as they're got a syncromesh.

Heel and Toe changing is a seperate thing all together.

It's about matching engine speed to road speed for the relevant lower gear you're about to engage.

Try going from 3rd to 2nd at 50mph without blipping the throttle - you'd almost head-butt the windscreen.

Blip the throttle first and progress/decceleration remains smooth and balanced.

 

[Dan 172]

Heel and Toe changing is a seperate thing all together.

It's about matching engine speed to road speed for the relevant lower gear you're about to engage.

Try going from 3rd to 2nd at 50mph without blipping the throttle - you'd almost head-butt the windscreen.

Blip the throttle first and progress/decceleration remains smooth and balanced.

I always use this on the bike, a quick blip of the throttle on every down change helps the rear wheel grip and not lock up under heavy braking.

Their are quite a few bike out there now with slipper clutches, which helps alot on the track.

In a car I can't be bother to mess about with anything like that, I'd rather concetrate on my line and apex.

 

[dan.clio]

This is interesting:

In addition, many modern vehicles use a "Drive By Wire" or Electronic throttle control system instead of the traditional mechanical throttle linkage. These systems have a safety interlock that prevents left foot braking. The car's ECU can detect when both pedals are pressed simultaneously and will immediately cut the engine power for safety reasons.

 

[MarkCup]

I always use this on the bike, a quick blip of the throttle on every down change helps the rear wheel grip and not lock up under heavy braking.

It was bike riding that made me appreciate the value of doing it, clutchless down changes made smooth and easy with a slight blip.

As soon as my Cup arrived I started practicing heel and toe downshifts - don't even think about that now, comes naturally.

Learning left-foot braking - now that's been hard work! Still got lots of work to do on my sensitivity. Getting my auto Omega soon will help me practice though - no clutch to bother with :approve:

 

[MarkCup]

This is interesting:

In addition, many modern vehicles use a "Drive By Wire" or Electronic throttle control system instead of the traditional mechanical throttle linkage. These systems have a safety interlock that prevents left foot braking. The car's ECU can detect when both pedals are pressed simultaneously and will immediately cut the engine power for safety reasons.

Thank f*** Renault didn't put this on RS clios.

 

[Yellow Dave]

This is interesting:

In addition, many modern vehicles use a "Drive By Wire" or Electronic throttle control system instead of the traditional mechanical throttle linkage. These systems have a safety interlock that prevents left foot braking. The car's ECU can detect when both pedals are pressed simultaneously and will immediately cut the engine power for safety reasons.

Sorry, but that's not true with my 182. whether other owners will agree or not I don't know. As soon as I hit the apex of a bend, it's on full throttle with my left foot dragging the brake to stop the understeer.

As for heel and toe braking, tried it from high speed and you can really tell the diffreence in the balance of the car if it's bumpy or slightly bendy road

 

[Dan 172]

I always use this on the bike, a quick blip of the throttle on every down change helps the rear wheel grip and not lock up under heavy braking.

As soon as my Cup arrived I started practicing heel and toe downshifts - don't even think about that now, comes naturally.

Learning left-foot braking - now that's been hard work! Still got lots of work to do on my sensitivity. Getting my auto Omega soon will help me practice though - no clutch to bother with :approve:

That's how I am on the bike, you don't even think about it.

I expect most (like me) need to get there lines right, before trying that on a track.
But I understand how it can make the difference, with drivers like yourself who know what they are doing on the track.

I've tried left foot braking a few times, but normally end up flying forward lol!

 

[dan.clio]

This is interesting:

In addition, many modern vehicles use a "Drive By Wire" or Electronic throttle control system instead of the traditional mechanical throttle linkage. These systems have a safety interlock that prevents left foot braking. The car's ECU can detect when both pedals are pressed simultaneously and will immediately cut the engine power for safety reasons.

Sorry, but that's not true with my 182. whether other owners will agree or not I don't know. As soon as I hit the apex of a bend, it's on full throttle with my left foot dragging the brake to stop the understeer.

As for heel and toe braking, tried it from high speed and you can really tell the diffreence in the balance of the car if it's bumpy or slightly bendy road

Its just what i found on google.

I thought that all the newer RS Clios had non cable throttles?

 

[steven.m]

To be honest, i'm not entirly following what this left foot braking malarky is, to me it would be braking with the left foot instead of the right.

I have just looked up wikipedia to see what it said. http://en.wikipedia.org/wiki/Left_foot_braking

An example it used is in a race situation where your cornering under power you brake with your left foot to control the understeer, but if your cornering under power you want to go faster so why brake at all? Am I missing something here? It says it is to control understeer etc but if your understeering then just lift off the throttle a little to bring the front end in?

 

[C.slicker]

All mk2 ph2 clios have FBW so in theory you couldn't do it any of them?

I am sure thats b****cks...



To Steven.m:

I think the idea with left foot braking is that the car is constantly under control as their is a constant input. There is never a time when the car is just coasting. This gives better times when its mastered.

Sam

 

[MarkCup]

An example it used is in a race situation where your cornering under power you brake with your left foot to control the understeer, but if your cornering under power you want to go faster so why brake at all?

When you do it mid-corner, you're not using the brakes to slow down, but to control the 'attitude' of the car - i.e. where its weight sits. The slightest brush of the brake pedal with your left foot will transfer a little weight forward which can control understeer, but you're still on the throttle with your right foot, and still accelerating (or maintaining a constant speed at least).

This quote from a successful racer in a book I read recently which was discussing the fine arts of braking and entering a corner (I forget who it was now) sums it up for me...

"I find it amazing how many people think the brakes are for slowing the car down".

To any track noobs, your approach to finding lap time should be...

Find the optimum racing line (biggest gain)
Work in each turn so that you are on the power and accelerating out as soon/early as is possible (good gain)
Braking and entering (slight gain)

In other words, practice heel and toe/left-foot braking all you want...but it's a waste of time and effort if you've not mastered first two.

 

[Russ_16v]

that was my dads techique,he taught me to drive,and his technique was the only time your foot should be off the pedal is when its moving between braking and accellerating,but he can heel and drive alot better than me but he is an ex rally driver lol


just remember to be smooth,be consitant,brake and slow down too much and you loose your momentum and have to gain that bk,not enough braking and you enter the corner too fast and missing the best moment to get bk on the power to get the best exit speed,just takes practice and see wat works best for you,i personally try to keep smooth,not many sharp streering movements,keep the momentum up and not to brake too hard,and that seems to give good lap times,but iv seen people go gung ho and get great lap times and really man handle there car,right on the edge as it is,which is great fun lol

 

[MarkCup]

True.

The harder I try, the slower I go - took me a few late night sessions of watching back videos to understand why...it's all in the balance and power application.

If I just chill out and sit back and focus on being smooth, I'm so much quicker.

 

[Russ_16v]

and as you know matey that is the key to fast lap times

its bloody fun getting all out of shape though lol,not the fastest but still fun

 

[Tony Hunter]

Carry on,I'm just having a little at all this

 

[Russ_16v]

Carry on,I'm just having a little at all this

lol not suprised matey,whats ur ten pence then?

 

[Graham Gooch]

There is another use of left foot braking, although its only for turbo cars, whilst braking keep the throttle pinned, thus keeping the turbo making boost for a good slingshot out of the corners.

Used to be used by rally drivers before anti lag came along.

 

[Tony Hunter]

You've said it all Russ'
smooth
balance
momentum
line
all=exit speed.Fast in slow out.Slow in fast out.
Somebody said they had trouble lfb,put a marble in your shoe to get the feel of the pedal

 

[Graham Gooch]

I always use this on the bike, a quick blip of the throttle on every down change helps the rear wheel grip and not lock up under heavy braking.

Their are quite a few bike out there now with slipper clutches, which helps alot on the track.

In a car I can't be bother to mess about with anything like that, I'd rather concetrate on my line and apex.

Although to me, slipper clutches promote lazyness.

Proper throttle downchanges for the win!

 

[Russ_16v]

You've said it all Russ'
smooth
balance
momentum
line
all=exit speed.Fast in slow out.Slow in fast out.
Somebody said they had trouble lfb,put a marble in your shoe to get the feel of the pedal

cheers matey,glad iv been taught the right ideas

i know people (including me sometimes) who drive without shoes to get a good feel of the pedals

 

[Graham Gooch]

^ thats why racing slippers as so thin on the sole.

Don't get caught without shoes though make, there is an old draconian part of the law that states its illegal and punishable by points! unlikely but its possible.