Imagine you’re on the track and you’re closing in on your best lap time ever. You hit the last left-right bend combo on the circuit, a tight and super fast S-curve. It’s the last obstacle separating you from the finish line. You enter the first left bend at optimal speed. You then instantly flick the steering wheel to the right in anticipation of the next turn and bury the throttle because you really want to nail your record time. All of a sudden, your car goes into a state of rejection, spinning out of control.
Chances are, you have just experienced “sideways weight transfer”. The weight of a car shifts to its outside wheels when cornering, which in sudden changes of direction (i.e. from left to right), the load applied to the outside wheels is massive, especially at high speeds. It’s important to steer and apply throttle in a smooth manner controlling the momentum of the car’s weight.
There are 3 types of weight transfer:
- The first being sideways weight transfer, as explained above
- Rear weight transfer which is caused by acceleration
- Forward weight transfer which is caused by braking
Remember folks, keep it smooth and always think ahead before negotiating any corner.
Stay tuned! Pun intended.
elwehbi@brakebanzeen
This post was written by guest blogger, El Wehbi, from the automotive blog Brake Banzeen! To read more of his work, visit brakebanzeen.com.
Manaf J Hoss
Dec 28, 2009 -
Hmmm, I like the idea, but the information is very weak…
You have to realize that the way your car is balanced is basically how it’s going to react. You have several types of car types, FR, Front engine rear wheel drive, FF, Front engine front wheel drive, MR, Mid engine, rear wheel drive, and finally AWD, all wheel drive or 4×4…
Each have their benefits, and disadvantages.
Majority of entry level cars use FR, Super cars are mainly MR and AWD.
Now what does all this have to do with weight. To be honest the distribution of weight on your car dictates the angles you approach and leave corners. From this you have three types of steering, Over-steer, or the tendency to cut sharply into corners, under-steer, a tendency not to turn enough in a corner, and neutral steering, goes where you point it to go…
Majority of FR cars suffer from under-steer, MR vehicles over-steer…
When taking a corner you have a whole lot of physics working, and if you got all the right upgrades you should be able to turn where and when you intend to do…When you take a corner you have a shift in weight from side to side. This exercises your Sway-bars, shocks and even wheels and tires. Let’s take a closer look at what happens, let’s say you would like to turn right, what really happens normally…The wheel is turned to the right, the weight of the car is shifted to the left, this depresses the left coil-over and the sway-bar starts to work for the right side is lifted upwards. This also releases pressure from the right wheel/tire and places this on the left wheel/tire. If you have ever looked at the tires you would notice there is a shoulder on the side of the tire but doesn’t really have contact on the road, this extra area is used in instances like this added more traction on corners so you minimize under-steer…Air pressure plays a part in this contact area touching the road…
Now back to weight distribution, we live in a non-perfect world but all demand perfection. As mentioned before you have FR, FF, MR, AWD, now why is this important, well where the engine sits dictate where most of the weight will be and in a whole how the car will react…
FR are mainly 60/40, MR 50/50, FF 60/40 and AWD mainly 50/50…
What are these? They are where the distribution of weight is on the front/rear tires. The closer you get the 50/50 the closer to neutral-steering you will have.
I attending a track day and I will never forget what our instructor said. She said cars are like Men, they can’t do more than one thing at a time…And it’s true…If you try and do multiple tasks you will suffer from loss of traction. When you accelerate the weight is shifted to the rear, removing some of the weight off the front tires. When you brake, the opposite effect takes place. And we all remember what happens when we try and turn…So let’s take two tasks and mix them up, a simple mistake we all do is brake into a turn, now what is going on during that simple maneuver. We already know that the weight of the car is shifted forward, placing additional pressure on the front tires, then while cornering the weight is also shifted to only one tire, so basically we have 60% of the cars weight being held back by one tire. Not good, this could lead to drastic over-steer and the rear of the car to be swung out. This will cause a spinout and you will have to work hard to regain your position…Lets take it the opposite way, you accelerate during a turn, well, the opposite effect happens. The weight is lifted off the front making turning very difficult resulting in under-steer…
When taking a corner or even tackling the entry or exit you have to be CALM and not push more than the car can handle. Be smooth and it is possible for you to stay competitive. I once say a stock Audi TT keep up with a Porsche GT2. Both are classes apart, but the driver of the TT was a lot smoother and did not waste time or energy around the corners…
I know there is a lot of information to understand here, but the simple task of turning is not that simple. It is always best to reduce sprung weight of your car (IE light wheels, tires, shocks, brake rotors, etc) and balance it to be as close to 50/50 as possible. Power is only PART of the equation, not the whole solution…Only then can you really appreciate the true thrill of driving…
elwehbi
Dec 28, 2009 -
Manaf J Hoss:
Thanks for the detailed info. I appreciate the fact that you took the time to reply and paint a much deeper picture of the topic at hand. In my columns, I am not instructing people on how to drive but I am just trying to shed some light some on the things they should be informed about. As you mentioned, a lot of factors will play into the set up of a car for the track. Each machine has its own limitations and potential. I try to keep it general just so people can be aware of these things without overwhelming them initially. This would also give them the chance to ask a professional, whenever at a circuit / track day, who could help them set up their cars to suit their individual driving styles.
Great reply and thanks again!