...I was making progress as the advanced drivers say.....thought i would left foot brake a touch as negotiated a roundabout......and the engine cut its power for 2-3 secs!.......pain in the butt.....

I only have ASR....can this interferance be dialled out using VAG com?

Keith

Drive by Wire - Application of the clutch or brake pedal cuts engine RPM.

When you press the brake it cuts off the fuel so you can't left foot brake.... :(

EDIT: Or what Stu said! lol

And it probably can't be disabled with VAGCOM - not even sure if you can do it by other means without significant expense etc

Drive by Wire - Application of the clutch or brake pedal cuts engine RPM.

Actually pressing the clutch doesn't as when i had one for the day on Saturday i was blipping the throttle on down changes with clutch pedal pressed.

I

I believe it's a safety measure to guard against a stuck throttle.

And an interesting way to demonstrate this safely is to dial up and hold a few k rpm's whilst the car is in neutral and then press the brake pedal. It doesn't kill power when the clutch is disengaged, just when the brake pedal is depressed

Chris

Yes my mistake I was confusing myself with Cruise Control.

It'll probably drop boost, that's what happened with my old Saab 900 T

Was looking at the brake pedal when fitting my clifford (needed a connection for my IS4), i noticed that there is several wires coming off it. My guess and ONLY a GUESS, if one was say severed it may stop the ecu killing the power. Just an isea and ONLY and IDEA. I hold to responsibility for any one cutting wires.

Dont do that, two of the wires are for the lgihts, two are a signal for the engine ECU. This is used for more than just the engine limit. It will bring up the EML as the brake switch is used in the setting of the learned values of the engine ECU (also known as rediness codes)

I've come across this cutting out as well with VAG TDI engines.

The engine will come back on boost if you keep your left foot on the brake and press the accelerator again.

It makes it hard to get the back end out (I assume this is the reason you want to left foot brake) because it takes a lot of timing.

I also used to left-foot brake when I was planning an overtake- plant the throttle, keep the speed with the brake and, when the road is clear, come off the brake and away 'cos the engine is on full boost.

Hi

Definately cuts more than boost as if one of my learners is pressing the gas instead of the brake (it has only happened twice in 3 years but it wakes you up when they do it), the car is easily slowed down on the brake in any gear.

Left foot braking is not really an essential in these cars though. The lag is minimal. The technique was originally devised by drivers of cars with small engines and turbos the size of bin lids. Anyone here remember turbocharging 1980s style?

Chris

Left foot braking is a big no no!! I am a 26 year old Advanced Police Driver and it serves no use other than to unbalance the car entering in to a corner. All of the weight is transferred forward over one of the front wheels. (depends which way you are turning as to which wheel the weight is transferred too) Set your speed before the corner and maintain that speed round the corner. This keeps the car balanced and the grip to all four wheels. No hedge visits!!

Please buy the Roadcraft book and have a read. That is the system of car control Police use and I live by it now. I like my VRS's body work unmodified!!

Left foot braking is a big no no!! I am a 26 year old Advanced Police Driver and it serves no use other than to unbalance the car entering in to a corner. All of the weight is transferred forward over one of the front wheels. (depends which way you are turning as to which wheel the weight is transferred too) Set your speed before the corner and maintain that speed round the corner. This keeps the car balanced and the grip to all four wheels. No hedge visits!!

Please buy the Roadcraft book and have a read. That is the system of car control Police use and I live by it now. I like my VRS's body work unmodified!!

Hi

Skillfully done, left foot braking does not result in slowing the car down or transferring weight forward, merely allows the driver to load the engine without putting that power through to the road. IMO not really a road technique, but for some older turbo cars, pretty much essential if you are keen to get along without big waits for lag. A good way to melt the brakes as well.

Also, two versions of balanced. Balanced as in neutral weight distribution, ususally acheived by small amount of gas through corner to maintain constant speed OR balanced as in similar slip angle front to rear requiring the use of throttle in corner or trail braking to set up car for corner.

Using limit point analysis in a long tightening corner may cause you to need the equivalent of trail braking, worth practicing so you know what happens. Use of same technique generally allows for acceleration out of corners so if done "enthusiastically" a rear steer balance can be had getting the car loser to the latter description of balanced on the corner exit.

Fabias are understeer city, so a dab of trail braking to get the tail working for you before getting back on the gas is quite helpful sometimes and does not compromise stabiltiy to a dangerous extent unless you are clumsy with it or too slow back onto the gas.

I am ploughing my way through an up to date copy of Roadcraft at the moment. Glad to see it moving into the 20th century, finally allowing brake gearchange overlap. RoSPA dont like it though, from what I have read.

Chris

Glad I found this thread......the other night I was trying to get some tail-gater off my rear bumper so applied a bit of left-foot braking offset with a slight increase in acceleration...when all of a sudden power was sapped....got a hell of a fright i can tell you! Least I know now it's by design. Other than that I would never use left-foot braking, in an emergency situation, it could cost you your life when your instincts take over.

my Lupo does it too, it's standard across all VAG DBW systems

I am ploughing my way through an up to date copy of Roadcraft at the moment. Glad to see it moving into the 20th century, finally allowing brake gearchange overlap. RoSPA dont like it though, from what I have read.

Yeah it's allowed (as is rotational steering) but in the video they say you have to have a good reason for doing it and it's not an excuse to cover up late planning and poor observation. Interestingly, the HPC take a more relaxed view on BGOL and welcome the use of trail braking, heel 'n' toe and left foot braking where they can be used to gain an advantage on the road without compromising safety

Chris

Chris GB... I remember the big turbo 80's cars you talk about, my friend has just bought a plaything.... mitsubishi starion turbo.... that car is a definition of turbo lag! lol....

Left foot braking doesn't transfer any weight on to the front wheels when pefrormed in accomplished fashion. Braking and additional power compensate each other at the front with the net effect of just braking on the rear wheels.

Unfortunately the number of people who are talented enought to left foot brake properly are few and the public highway is not really the place to practice your technique!

Whoops!

I hadn't read the second page of posts!

A little dab of handbrake works a treat though.

Only joking here. A quick lift off the throttle makes mine come back into line from the usual understeer quite well enough.

I've got an auto - tried it once and only once - nearly went straight out the windscreen - your left foot is too used to going hard on the clutch.

i tyred this and nearly died lol :lol: