Scaling to Win

Scaling is not about a magic setup but about establishing a base line setup and your ability to repeat that setup and then recording your race winning numbers. Proper chassis setup requires that the weight balance is set correctly for the car, driver and track conditions. In order to achieve proper and repeatable weight balance, a calibrated set of scales need to be used. Grain scales have been used for many years but they are bulky and take up lots of shop space. Electronic scales have the advantage of being less bulky, easy to handle and store away, plus show you all your wheel weights and percentages without having to have a calculator, paper and pencil. Electronic scales continue to advance and now are available wireless at a reasonable price.

Spend a few minutes with a good level and straight edge and mark four spots on the floor where you can place the scale pads each time you scale the car. If you can't find a spot on the floor without low spots you can use the adjusters on the scale, roll off levelers or shim the scale pads. Be sure all four pads have the same height and are level side to side and front to rear. Mark the pads or trays with LF (Left front), RF (Right front), LR (Left rear) and RR (Right rear) so that you can repeat the process accurately every time.

Before you begin the scaling process you should make sure that the car is race ready. If you're running a pavement car with a front sway bar it should be disconnected. Zero the scales, then jack up one side of the car at a time and slide the pads underneath the tires. Use a stop to keep the car on the scales. Do not place the car in gear, as this sometimes can cause a bind or move a pad when lowering the car on the pad and we want everything free of binds. Bounce the car front and rear and side to side in order to work out any binds in suspension, shocks or springs that have jumped out of pocket. Repeat the settling procedure consistently as this will help you obtain repeatable results. Repeat after each time you lift the car off the scale pads or make an adjustment. Personally, I like to see the driver in the car during the scaling process as they have a large effect on the numbers. Having them in the car insures the most accurate results. Check with your chassis builder to see if their recommended settings are with or without the driver and adjust accordingly.

Check that the front to rear balances is correct and that the left side and total are to chassis manufacture's and track specs. If not, then move or add ballast until you achieve the proper numbers desired. Adjust the ride heights if you have to move ballast. Turning weight jacks or coil over adjuster nuts will not move the left side or rear weight. To make changes to the left side or rear you must physically move ballast.

Now you can check the cross weight. If you want to add cross weight put a turn in the right front and left rear and take a turn out of the left front and right rear. Do the opposite on each corner to decrease cross percentage. Adjusting all four corners will help maintain your ride height. Lighter weight rear springs may require more rounds to achieve weight transfer then heavier front springs. Record your final settings and you are ready to go. Oh, and pavement racers, remember to connect your sway bar and set its preload.