Cornering Basics Part 5 - Controlling the Car

[R_U_LOCAL]

Controlling the Car Through the Corner

I mentioned in part 4 that there was a final part to this series on cornering, and here it is.

In this last section on cornering, I’ll look at how you should operate the car’s controls as you drive through the corner. I’ll start by assuming you’ve done everything else – assessed the corner, brought the car down to the correct speed, selected the right gear, picked out your line – and you’re now just at the point where you need to drive the car through the corner, following your chosen line.

Let’s make this as simple as possible. There are only two main controls you’ll need to operate.

1. The steering.

2. The accelerator.

In operating these controls, the key aim is to maintain vehicle balance – we want to accelerate out of the corner as quickly as possible whilst maintaining grip with the road surface. This involves balancing the two main forces which are competing for the tyres grip – turning the car and accelerating the car.

When you first turn the wheel, bear in mind the principles which I described in this old post on steering – start the turn of the wheel slowly to “hint” to the car that you’re about to start turning, and then when the car starts to turn and the suspension has “taken up the slack”, you can increase the speed at which you apply the steering lock before slowing the application when you’ve applied the right amount of lock.

One thing to bear in mind is that a car’s suspension isn’t just designed to give a comfy ride or to keep the wheels attached to the car. Suspension – particularly rear suspension – is designed to help the car to negotiate corners as safely and efficiently as possible.

Using some very clever links and angles, engineers nowadays design rear suspension to include a small amount of “passive” rear-wheel steering, which means that when the car is cornering and the suspension is compressed by the cornering forces, the rear wheels will steer slightly and help the car through the corner.

It’s very subtle, but has a very real effect, and to take full advantage of this effect, it’s important that whenever you steer through a corner, you should accompany the steering with a press of the accelerator. Many people know that you should accelerate out of a corner, but most people don’t know exactly when you should press the accelerator.

The answer to that question is very simple:

You should start to press the accelerator at exactly the same time that you start to turn the steering wheel.

This might seem too early – if you’ve any track driving experience, it will definitely seem too early, as a good track driver may still be braking when they start turning the wheel – sometimes right up to the corners apex.

But, as I’ve said many times before, driving on the road is not track or competition driving, and on the road, we should have sorted our position, speed and gear before actually getting to the corner.

So, the instant you start to turn the wheel, you should balance the steering by pressing the accelerator. In a tight corner, you should only press it gently at first, to balance the car and make use of the passive rear-steering. As you approach the apex, and the corner starts to open, you can press the accelerator a little harder, and as you start to take the steering lock off and the road starts to open up, you can press it harder and harder to match the straightening of the front wheels.

I used to tell students to imagine there was a piece of string connecting the steering wheel with the accelerator. As you turn the wheel – the accelerator is pressed – almost as though they are one single control which applies steering and accelerator simultaneously.

In a faster, more open corner, you can press the accelerator harder and fire the car through the corner with a good amount of firm acceleration. Trust me on this – it’s one of the most satisfying feelings it’s possible to obtain whilst holding a steering wheel! The key – as with tighter corners – is to start pressing the accelerator immediately when you start to turn the wheel.

The slowest point in a corner should be the point where you turn in. From there, pressing the accelerator will gradually build up speed whilst settling the car on to its rear suspension, taking full advantage of the passive rear-steer and giving you maximum steering effect.

Try it next time you’re out for a drive. Take a bit more speed off for the corners, and accelerate earlier – you’ll be surprised how much better your car will feel through the bends!

[R_U_LOCAL]

Jon1967x said:

Be good if you could expand on front v rear wheel drive and how much is to initially avoid engine braking and how much is to move weight to the rear and commence a smoothly increasing acceleration phase

The technique is essentially the same, irrespective of whether the car is front, rear or four wheel drive.

The first thing to remember is that we're not talking about handling a car on the limit here, where we're looking to manage understeer or oversteer. This is a road technique which works best at speeds ranging from normal up to just below the limit of the cars grip. If a car is understeering, for instance, the correct response would be to lift off the throttle to transfer some weight forward onto the front wheels, increasing their grip and reducing the understeer.

Instead, what we're looking to do is to balance the car so that it's starting to accelerate the instant you turn the wheel, and continues to accelerate at an appropriate rate as you negotiate, and then exit the corner.

Accelerating as you turn the wheel will, of course, transfer some weight rearwards which gives increased grip to the rear wheels - an advantage in RWD cars and a disadvantage n FWD cars, but because we're staying within the cars limits, there will be sufficient tyre grip available to manage the weight transfer.

The real advantage of applying the accelerator early is that the previously mentioned rearward weight transfer combined with the cornering forces, results in the rear suspension's tendency to create a small amount of rear-wheel steer to work at it's most efficient - the car reacts better to the steering with a little (and sometimes a lot of) acceleration.

To put it in very simple terms, try going round a corner whilst decelerating - with no throttle whatsoever, and then try going round the same corner with some acceleration. You'll find that the car just "feels" better whilst cornering with a little acceleration - keener to turn, more responsive, dare I say it - more fun.

I used to take students out in a wallowy old Mk1 Discovery to demonstrate the technique. A car with soft, compliant suspension and long wheel travel gives a much more pronounced reaction to cornering with and without acceleration. Try it in a soft old 4X4 if you ever get a chance and you'll see what I mean.

[R_U_LOCAL]

anonymous said:

[redacted]

Keeping some braking on as you turn in to the corner may be an effective method to encourage the front wheels to turn in initially, but I wouldn't recommend it for the road. On the track, you've little else to think about other than your physical actions in the car and little else to worry about other than your ultimate speed through the corner and onto the next straight. So for track driving, trail braking up to the apex whilst downchanging with a heel/toe technique is probably the best approach.

On the road, however, I'd advocate sorting everything in a straight line before you get to the turn-in point as previously described. Perhaps the only tiny change I'd make if I were drivng a rear or mid-engined car would be to make the very first initial turn of the wheel with no throttle input. This means that, after braking and changing down, there is still a little forward weight transfer (the throttle is shut so there is still a little retardation from the engine) to assist the front tyres in starting the turn.

Once the car has started turning, (by which I mean literally a fraction of a second after you've started to turn the wheel) start gently applying the throttle until you're at the apex and then increase the throttle input as the corner starts to open up.

[R_U_LOCAL]

anonymous said:

[redacted]

I don't agree (you didn't think I would, did you?)

As I've stated probably hundreds of times, track driving and road driving are so different as to almost be two completely different skillsets - like comparing driving and motorcycycling, for instance. There are, of course, some similarities between driving and motorcycling - engines, clutches, tyres and stuff, but the skills required to do both are very different.

I've driven quite a bit on track (I have a dedicated track car which is used regularly) and I've done a little road driving. Despite my background, When I started track driving, I had to completely re-evaluate my driving and make a number of significant changes to my driving style, not least of which was to brake harder and later than I was initially comfortable with, and to change down and match engine revs at the same time.

Your primary aim on track is to carry as much speed into, through and - most importantly - out of every corner.

On the road, there are far too many additional variables and considerations for speed to ever be the primary consideration.

I have never felt tempted to transfer any of my track techniques to the road. I'm perfectly happy with my road cornering technique, and although it may sound like a slow and ponderous approach when you're reading about it, when you experience it put into practice properly it really isn't - I can make significant progress using my technique whilst still maintaining adequate safety margins.

I understand your point, and if you're happy with your technique, then stick with it. But at least have a go with my approach next time you're out for a drive and let me know what you think.

[R_U_LOCAL]

Nigel_O said:

Fair point

However, if a bend can be taken comfortably and safely at the speed you had chosen to do on the straights, then there is no benefit to accelerating out of the bend

I think the process of accelerating out of bends is fine if the road is clear, you're "making good progress" and are choosing to disregard the posted speed limits. However, in everyday driving, surrounded by other drivers and a multitude of hazards, accelerating out of a bend is pointless and may even be regarded as overly-aggressive by the car in front, who you will no doubt catch up with very quickly shortly after the bend

I should have mentioned this point in my original post, so thanks for the reminder.

There are plenty of corners which are well sighted and which visually "open up" before you actually get to them. If you're maintaining a chosen speed, then you'd think that all you have to do is turn the wheel and maintain a constant throttle, wouldn't you?

Think about that for a moment - your car is travelling along at a constant speed. As soon as you turn the wheel, lateral forces are generated through the friction with the road surface and weight is transferred to the wheels on the outside of the turn. If you do absolutely nothing with the throttle, the increased frictional forces will cause the car to slow down. Not by much - granted - but by a few miles per hour at least. More if the corner is particularly long.

To counteract this reduction in speed, you should apply a small amount of gas - by accelerating, you counteract the cars natural tendency to slow through corners and maintain your chosen speed.

So, accelerating through bends is important, even if you just want to maintain a constant speed.

[R_U_LOCAL]

gdaybruce said:

a) When tackling a sharp bend on a steep downhill, any application of throttle can have you travelling much quicker than you might have planned. I tend to stay away from the accelerator until I’m past the apex and the bend is opening up.

Yes, a slightly different technique is required for bends on steep hills, but the principle of accelerating through the corner is still valid - it's just the execution which is slightly different.

Some downhill bends will require braking, followed simply by a release of the brake pedal on turn-in. The downhill gradient will be enough to cause the car to accelerate slightly without any application of the throttle until, as you say, the bend opens up from the apex.

On steep downhill roads where there are a series of bends, you might even need to keep the brakes on around the corners, using the principle of braking more firmly in between corners, and less firmly through the corners. The car will still be accelerating very slightly even with some brake application, but modulating the brake pedal pressure can help maintain maximum balance.

gdaybruce said:

b) Conversely, when going uphill around a sharp bend some acceleration is necessary but if pushing on it’s easy to generate understeer as acceleration adds to the weight transfer to the back axle. I’ve tried my best effort at the rally technique of approaching fast and throwing the car into the bend and then applying lots of power to break the back away. It’s great when it works but is hardly suitable when anyone else is about!

It all comes down (again!) to balance and a degree of "feel". On an uphill stretch, less braking is required - and sometimes no braking - because the gradient will slow you sufficiently well using only acceleration sense. You're already pressing the gas pedal due to the uphill, so it often feels much more natural to accelerate early into uphill bends.

Mid-bend crests add a further interesting dimension, particularly if you're pressing on. Experiencing the car "going light" just as you're fully committed to a quick bend can suddenly require your full attention!

[R_U_LOCAL]

Jonsv8 said:

The weight transfer will be very different though due to gravity v power or braking. Downhill gentle braking but still physically accelerating will still have a forward weight bias in the car and as such you won't get the rear steer effect.

Thats why I advise relaxing or releasing the brakes on turn-in. There will always be a forward weight bias due to the incline, but you can manage it to your best advantage through intelligent use of the brakes. Releasing the brakes and letting gravity do the accelerating will still transfer some weight towards the rear - just not as much as through normal acceleration.

[R_U_LOCAL]

My old post on vehicle balance here:

A Question of Balance

[R_U_LOCAL]

anonymous said:

[redacted]

I think it's pretty close to the point of the discussion.

Advanced driving is such a broad term, but I've been clear on two points in the post title. Point one is that it covers the basics of good cornering. Point two is that it is the fifth post in a series looking at all aspects of basic cornering skills.

Of course there are more advanced techniques, depending on your skill level, experience, the type of car you drive, whether you're on road or track etc, etc.

But for a large proportion of drivers, the simple change from being off the throttle through a corner, to introducing a little acceleration through a corner can be an absolute revelation.

Lets not get too tied up in the minutae of trail-braking, balancing a car on the brakes on turn-in etc. these techniques all have their place, but in my series of posts on cornering basics, If a few drivers have learned to set their speed correctly for a corner, pick out a good line and apply some acceleration whilst cornering, then there's probably a few more better drivers on the road, which isn't a bad thing.

Perhaps I should do a post on very advanced cornering for those of you who feel this series is too basic?

Edited by R_U_LOCAL on Saturday 2nd May 13:22

[R_U_LOCAL]

Thanks for explaining my post to me.

Now, please carry on and explain how a post describing how to improve a vehicles balance through a corner isn't directly related to safety.

[R_U_LOCAL]

Really?

Jonsv8 said:

I don't think anything in the original post was directly safety related...

[R_U_LOCAL]

anonymous said:

[redacted]

You beat me with a crafty edit.

I agreed that the original post was part of a series on the basics of cornering. i.e. All those who drift off (no pun intended) into posts about trail braking, limit handling etc have missed the point of the original post.

But like you say - whatever.

[R_U_LOCAL]

We'll have to agree to disagree then.

My opinion is that trail braking is generally not necessary on the road, whatever configuration of car you're driving.

If your corner entry requires braking to maximise front-end grip at turn-in, it may be an indication that your entry speed is too high and/or you haven't assessed the severity of the bend correctly.

Don't think, however, that I'm suggesting your technique is "wrong" - I usually try to avoid "right" and "wrong" in discussions on different techniques - if it works for you, then stick with it. For someone starting down the road of improving their driving, however, i believe my technique is a good, safe one which also, if executed well, feels like a good technique.

[R_U_LOCAL]

Yes, quite a bit.

The technique I'm advocating may not be for everyone - you need to think of it in the correct context.

For a driver who has only previously received training for licence aquisition, who has then gained some experience on their own, but is looking to improve, the principles of safe, quick cornering are much easier to master if they can be broken down into individual phases.

My objection to turning in on the brakes is that for someone who is developing their driving - going from everyday driver to something a bit more advanced - it requires too many seperate actions to be co-ordinated at once. Braking, changing down, matching revs, turning, smoothly releasing the brakes towards the apex, smoothly picking up the power and managing the shifting weight.

Try teaching that to a novice advanced driver and you'll completely lose them. One or two may have the natural ability to pick it up with some practice, but its far too much for most drivers to co-ordinate at once.

As I previously mentioned, these cornering posts, as with all the other stuff I write, is aimed at anyone - no matter what experience level they're at - who wants to improve their driving.

I could write seperate posts on how to drive all sorts of different vehicles with different engine and drive configurations, but I try to keep my advice as simple and straightforward as possible.

Do you have much experience with driver training/development?