Many of the articles you read in Circle Track cover chassis setup, areas of critical concern, one at a time and over the years we have tried to refine and update the information. In this installment, we will present the top chassis challenges you will face when setting up your race car. If you can manage to refine these 13 challenges, then we believe you will be well on your way to success.
In the example shown above of a Drag Link system, we see why it is designed as it is with
1. Steering Challenges
A correctly designed steering system is an essential element in the make-up of a winning stock car. The amount that each wheel turns as the car is steered can have a major impact on how your car will handle.
The amount of static front end toe you need largely depends on the size of the racetrack, the banking angle, and the type of tire being used. Regardless of the amount of static toe-out you use, the toe numbers can change as we turn the steering wheel.
If our car gains toe when it is steered then we have what is called Ackermann effect. If our car looses toe when it is steered, we have reverse Ackermann. In today’s race cars, we do not need the Ackermann effect. Static toe provides all of the required difference in steering angle we will need to negotiate the turns.
This is a very clever idea we came across. This team drilled and tapped the spindle and we
2. Spindle Challenges
Many times we are faced with incorrect arm angles for proper Moment Center design because of a spindle that is either too short or too tall. If we can find a spindle with different dimensions, we may be closer to having the correct arm angles.
If we change from a 73/4-inch tall spindle, with an offset of 31/2 inches from the bottom of the spindle to the center of the pin, to an 81/2-inch tall spindle with a 31/2-inch offset from the bottom to the pin center, then we have raised the upper ball joint by 3/4-inch and not changed the lower control arm angle.
We can also install a 91/4-inch tall spindle with a 41/2-inch offset from the bottom to the pin and gain 1/2-inch of height of the upper ball joint while lowering the bottom ball joint by 1 inch. This does two things, it increases the upper control arm angle and also reduces the lower control arm angle.
At any rate, be aware of the different spindle designs related to the changes you may need to make to refine your MC design. Always keep in mind that spindles are very easy to change and you should never get locked into using a specific spindle. Rather, install what will make your car work better.
Be very careful to align the brake brackets before welding. Check them carefully after wel
3. Brake Challenges
In my experience, you can get all of the information concerning the proper choosing and use of brake components for your type of racing from your racing brake supplier and/or manufacturer. What is probably more important than components is the installation of the brake brackets.
This is an area where brake pros can’t help you. Many times we see where a car builder or team will hastily install the brake caliper brackets and not take the time necessary to insure the proper alignment and spacing. This will provide problems that are impossible to fix unless we address the real problem.
Take the time to do a good job of aligning the brake mounting brackets so that the pads will be perfectly parallel to the rotor and that the pads are spaced equally on each side of the rotor. This will provide smooth and efficient braking from now on.