Nascar: What does a wedge adjustment do to a car and how?

Think of a stable, four-legged table where the weight is evenly distributed among the four legs. If you tuck a small piece of folded paper under one of the legs, the table will wobble. Now the wedged leg and its diagonal leg carry more of the weight than the other two legs.

The same thing happens with a race car.­ Compressing the spring of a left-rear wheel or adding wedge puts more of the car's weight on that corner. This adds pressure to that end of the car just like putting the paper wedge underneath the table leg. As with the table, the corresponding diagonal corner of the vehicle gets more of the car's weight. So if you increase the tension in the left-rear wheel, the left-rear and right-front wheels will hold a larger share of the car's total weight than the right-rear and left-front wheels.

The reverse happens if you reduce the tension on the left-rear wheel's spring or subtract wedge. In our analogy, that would be equivalent to cutting short a table leg. It would increase the weight on the right-rear and left-front wheels. This is why a crew may need to adjust only one wheel when a race car needs to add or subtract wedge.

The diagonally related weight between the left-rear and right-front wheels is referred to as cross-weight or simply wedge. It is often measured as a percentage of the vehicle's total weight. When more than 50 percent of the car's weight is on the left-rear and right-front wheels, the car is said to have more wedge.

What Does A Wedge Do

It makes the car looser or tighter, so it slides around more or is harder to turn.

You'd take wedge out if your car is too tight, and put wedge in if it's too lose.

Wedge tightens or loosens a car up. If you add wedge, you will tighten your car up if it's loose. If you take wedge out it will be looser if your car is tight.

the wedge potentially puts the cars suspension on an angle so that the car can corner smoother and faster.

Sure thing