Turn the steering wheel a quick half-turn. As you're crossing over the white line into the other lane, simply squeeze on the gas again. This transfers weight back to the rear wheels to maintain traction. You will be by the situation much quicker and safer than if you tried to brake. Try this demonstration with a friend. Have him put his arm out straight, palm up. Put your arm out, palm down on top of his hand. Push down slightly on his hand like the pressure on the front springs during braking. Have him push up slightly, just enough to counteract the pressure.
Now, suddenly lift your hands, which will remove the downward pressure. Your friend's arm will suddenly pop up into the air. Springs and the whole concept of weight transfer work the same way. When you suddenly accelerate, the front springs release their downforce. The front tire patches rapidly decrease in size. If you treat the accelerator as if it were a sponge, apply pressure as if you were squeezing water out of it.
Squeeze on the throttle smoothly, you will always have smooth weight transfer under acceleration. To begin braking, roll smoothly off the gas pedal and squeeze smoothly on the brakes. Treat the brake pedal like the accelerator, as if it were a sponge. If you are smooth on the brakes, you will transfer weight forward onto the front tires while still maintaining some tire patch, which means traction, on the rear wheels.
The way humans react, if you lift off the gas rapidly, you will also hit the brake hard. If you roll off the gas smoothly, you will also squeeze the brakes smoothly.
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When you do that, you will control the weight transfer smoothly and always have traction on all four wheels. That is the key to being in control. When you accelerate, the weight transfers to the rear of the car, taking weight off the front. What that means is, the rear shocks are compressed, expanding the rear tire patches.
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While that is happening, the front springs are releasing their downforce. How hard you accelerate or how smoothly you accelerate governs how much traction you have in the rear and how much traction you lose in the front.
When coming down the road at 40 or SO miles per hour and you are going to brake, you ease off the gas, and the weigh. This maintains traction front and rear. Consequently, if you accelerate too hard through a corner, the front end is going to push. It is going to understeer.
To get out of that situation, roll the throttle back on. The sidewall will also deflect and scrub off speed for you. It is not necessary to brake. However, if you are understeering and you don't gain front tire traction quickly enough, gently squeeze the brakes to transfer more weight fon,'ard and regain front tire traction again.
Say you are coming into a right-hand corner, and you have jumped on the brakes too hard. Under hard braking and hard cornering, the weight will transfer laterally from right to left and longitudinally from the rear to the front. It takes weight off the right rear tire, resulting in a smaller tire patch and less traction. It transfers weight to the left front tire, resulting in a larger tire patch and more traction.
However, the right front tire also has good traction because 23 braking has shifted the weight forward. The result of all this weight transfer is the back end can start to slide out. To correct for the rear wheel slide. The tires again are going to scrub off speed. If it is not enough correction, squeeze on the, gas a little to put weight back on the rear tires. Carry the slide through the corner.
If you jump on the brakes in the middle of a rear-wheel slide, you are going to make the weight transfer problem worse and are going to spin the car out. This will vary slightly with the size and type of tire as well as the car, but in concept it can be used for a base of reference. These examples are from a Formula Ford, as the rear tires are larger than the front tires.
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This shows the car at rest. All aspects of vehicle dynamics get back to the issue of weight transfer.
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The key to vehicle control is simply to transfer weight to the area of the car needing traction. When a car is turned right or left from its course of travel, a lateral weight transfer occurs. This causes the suspension to be compressed on one side and expanded on the opposite side. Normally, the curve is completed and the vehicle's chassis returns to lateral neutral. REAR REAR Under acceleration the front patch has changed little-but look at the tremendous difference in the rear imprints as the weight transfers rearward.
When negotiating a series of reversing turns, these weight transfers can have a cumulative effect. Each lateral transfer becomes more violent than the one preceding it. If this keeps going, the vehicle will spin out of control. A driver must consider what reaction the vehicle will have to the driver's xtion. Smoothness in steering, braking, and throttle is the only effective way to minimize lateral weight transfers. Tires can only perform at their maxi:num when doing one thing at a time.
You can only corner at maximum adhesion or. If you try to turn while accel 'fating at the maximum, the rear tires will almost certainly slide or start spinning. Imagine a big sponge under the gas pedal. Squeeze on the gas like squeezing water out of a sponge. Squeeze on. Ease off.
Never jam on the brakes, even in an ABSequipped car. Instead, smoothly transfer weight forward when braking. Imagine a huge sponge is below the brake pedal. Weight transfer, tire patches, and Ackerman steering geometry all go together. The tire patch is where the tire meets the asphalt. Tire patch is about the size of the palm of your hand. When sitting still, all four tire patches are about the same. As you accelerate, weight transfers to the rear, and compresses the rear springs, pressing down on the rear tire patch making it larger. At the same time that is happening, front tire patches are becoming smaller.
As weight transfers to the rear, it releases pressure on the front springs, which moves weight upward and backward. As you approach a corner and roU off the gas, weight starts to transfer forward, and next you squeeze on the brakes. All forward motion compresses downward on the front tire patches, making them larger and larger, making rear tires patches smaller and smaller.
As long as you let off the gas and brake smoothly, you will always have all four tire patches working for you. As soon as you start to turn into a corner, say a left-hand corner, the weight will transfer laterally across from left rear to right front, putting more weight on the front tire, creating more of a tire patch. The Ackerman steering takes over.
The more you turn the wheel, the tighter Ackerman turns, and helps to steer you into the COfnero One problem to keep in mind is if you turn the wheel suddenly to full lock, it is going to turn the outside front tire past the area of rolling friction. Tire patch size won't help the problem either. You will have to unwind the wheel a little bit to have rolling' friction.
When you're smoothly on the gas, the brakes, and the steering wheel, weight will transfer between all four wheels. This means the total traction and adhesion of the car will be greater than if you were rougher with the gas, brakes, and wheel.
Vehicle control is directly related to tire traction, which is directly related to tire patch size, weight transfer, and smoothness. The Right Mental Attitude o matter what we do in life, to do it well, we must concentrate on it. We must put our minds to it, and work to accomplish it. Driving takes more concentration than most drivers realize. Enforcement driving, like race car driving, requires the maximum possible concentration.
A key difference exists between an advanced driver and a beginning driver. The beginning driver does the basics right some of the time, while the advanced driver does the basics right all of the time. More than training and experience, the true difference between the beginning and the advanced driver is actuaUy concentration. Concentrate on driving percent of the time.