To determine whether your car is tight or loose upon entry into the corner, roll through t
Driver Steering Crutch
There are many mechanical crutches to talk about, but there also are many human crutches the driver can be fooled by when negotiating the racetrack. Sometimes these crutches allow a racer to complete a race without coming in to make major suspension tuning changes, but usually they are unknowingly used by a driver to get around the racetrack. More often than not, these crutches limit the performance of the driver and car.
The most common driver crutch arises as a reaction to the way a race car needs to be driven to get around the track. Simply put, as the race car enters the corner, the driver turns the steering wheel until the car reacts positively in the direction of the turn. Often, the driver will claim the car is loose in the middle of the corner and upon exit. But often drivers are not cognizant of the fact that they are turning the front wheels too much to the left to overcome a tight condition on entry to the corner.
Determining the track banking is as easy as laying a straight 10-foot bar on the surface a
To understand this, we need to add some information about the characteristics of tires in relation to traction. Tire engineers have learned that a tire will generate more traction at an increased angle of attack to the direction the car is turning. This means the front tires gain traction as the steering wheel is turned...up to a point. When the front tires are turned to an excessive angle of attack, they will give up all their traction, causing a severe push or tight condition in the race car. Normally, as the steering wheel is turned to muscle the front end around on a tight race car, the handling balance of the car is reversed as the front traction becomes greater than the rear.
Here is the scenario: As the driver enters the turn, he simultaneously backs off the throttle, applies the brakes, and turns the steering wheel. The steering wheel is twisted enough so the front end comes around. If the car is set up too tight, the front wheels are turned more than would be necessary if the car's handling balance neutral. Because of the excessive angle, the front-wheel traction is greater than the rear-wheel traction and the car begins to feel loose. This can happen so quickly that the driver will swear the car is loose.
The driver will feel a loose condition in the middle of the turn and the exit performance will suffer because, as the driver gets on the throttle, the rear wheels are likely to spin. This slippage increases the temperature of the rear tires, which, once the car is back in the pit and the tire temps are read, might fool the crew into thinking the car needs to be tightened up.
Changing the Panhard bar mounting point changes the rear roll center, which might be neede
Determining Whether Steering Crutch Exists
Here's a great way to quickly discover just what the handling balance really is for your car: Ask the driver to roll through the turn well below the maximum speed. The amount of steering input needed just to drive around the turn should be mentally noted. Then, get the driver to roll through the turn at near maximum speed without excessive braking or acceleration, again noting the amount of steering input required. If the steering input is higher at the increased speed, the car is set up too tight. Many drivers are very surprised at the outcome of this test. You'd be surprised how much time messing with the setup can be avoided by doing this simple exercise.
Why Your Car Might be Tight
In descending order of importance, here are some classic reasons your race car might be tight entering the corner.
• The rear springs are too soft. This is true especially with the right rear. This will make a car tight because the springs allow too much roll in the rear of the car, which binds up the front end, overloading the right front.