The term balanced setup refers...
The term balanced setup refers to a combination of spring rates, moment center locations, and other setup parameters that will result in both ends of the car wanting to do the same thing in the turns. That is defined as desiring to roll to the same angle. Once we can match up the two ends, the weight transfer is then predictable and consistent.
1. Lap times fall off considerably after approximately 20 laps while the leaders stay consistent.
2. The RF or RR tire shows excessive heat and wear compared to the other tires.
3. The LF or LR tire shows considerably less heat and wear than the other tires.
4. The RR tire shows extreme heat and wear from spinning off the turns
5. The driver uses excess steering input at midturn compared to other faster cars.
6. The car "snaps" loose just when the driver gets into the throttle.
As you make changes to cause the car to be more balanced, the crossweight percentage needs to increase to keep up with the changes. If you raise the rear Panhard bar or stiffen the right-rear spring to reduce the rear roll angle to match the front, the car will become loose if you do not also increase the crossweight.
When we change the front-to-rear...
When we change the front-to-rear percentage of total weight in the car, the crossweight needs to change to keep the car neutral in handling. This is a 2,800-pound Late Model with a 66-inch track width, a 56 percent left-side weight, and a 15-inch center of gravity running on a 12-degree banked track pulling 1.7 g's in the turns. The numbers in the chart were calculated using standard weight transfer dynamic formulas available in many books on the subject. The car is considered to have a balanced setup.
The process of balancing the car makes the LF tire work harder for conventional setups on dirt and asphalt, and it makes the LR tire work harder for the BBSS setups. Too many teams make adjustments that make the car more balanced only to back off because the car is getting too loose or too tight.
Weight Do's:
1. Weigh your car with the driver to know your exact weight distribution.
2. Level your scales, roll the car to take out all binding in the control arms, air up the tires to race pressures, and add all fluids before measuring the weights.
3. Make changes to the crossweight in the shop to know how a turn of the screw or ring affects the crossweight percentage.
4. Change all four corners when making changes to the crossweight percentage to maintain the correct ride heights. To put cross in, put turns into the RF and LR springs and take turns out of the LF and RR springs. The opposite takes cross out.
5. Make records of your weights. Use weights taken on the racetrack scales for reference only. Do not ever change your crossweight to match the track scales. They are almost never level.
Coilover springs are much...
Coilover springs are much easier to adjust when changing the weight distribution. Make sure there are no binds in the mounting points that will affect your readings. This mounting bolt needs a tapered spacer between it and the shock eye.
Some Weight Don'ts:
1. Don't build your setup around a particular crossweight percentage just because you have always run that number. Be open-minded in order to find a better combination if that is what you need.
2. Don't guess at the crossweight percentage in your car. The old way of jacking up the rear end with a large socket between the jack and the rear differential pumpkin and seeing how far off the ground the RR tire is when the LR tire is barely touching is way out of date.
3. Don't run the high crossweight range on high-banked tracks unless the banking falls off abruptly and there is a problem getting traction off the corners. And don't try to run the low range on the flatter tracks with bite-off problems like I did at one time. That is how I learned about the different ranges.
4. Don't move weight around in the car to effect changes to the crossweight percentage. Move the weight jacking devices or shim the springs in a stocker.
5. Don't try to match your crossweight to a competitor that is running well. His overall weight distribution and setup may be very different from yours, especially the front-to-rear percentage of weight. This setup stuff all works in combination, and each car's combination is necessarily different.
Weight data is a part of that bundle of information about your car that you need in order to be competitive. Don't be shy about experimenting with items such as weight distribution, and by all means, think outside the box.
Once you find that perfect combination that the car needs, you won't share it, just like no one shared with you. Then you'll know why it takes so long to be competitive. It takes getting to the point where you quit listening to your competitors and start thinking for yourself, no matter how long you've been racing.