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Corner Balance Calculator

Car Corner Weight Calculator

By Rob Robinette

This calculator takes your car's four wheel weights and calculates current weights and percentages and generates target wheel weights to achieve a 50% Cross Weight. A 50% Cross Weight will yield a balanced handling car, one that turns equally well in both directions. For information on corner balancing see my corner balance how-to and  this excellent article: Grassroots Motorsports » Understanding Corner Weights

Left Front weight:          Right Front weight:

Left Rear weight:           Right Rear weight: 

  <  Enter your current corner weights above and click the "Calculate" Button.

These are your current calculated weights:

Total Weight =

                            Front Weight = %

Left Weight = %                        Right Weight = %

                            Rear Weight = %

Cross Weight = %  (50% is optimal)

Left Rear Bite =

Wedge = %    Wedge Delta

These are your target weights which will yield a 50% Cross Weight:

Left Front =                     Right Front =

Left Rear =                      Right Rear =

Cross Weight =   %

Left Rear Bite =

Wedge = %   Wedge Delta

You need a nice, flat and level surface for the scales. I highly recommend using a laser level to confirm the 4 scales are level to one another. Even 1/4 inch difference will make a difference, especially if you have stiff springs on your coil overs. I used a laser level to project a horizontal line above the scales and then stood on each scale and placed a ruler on the top of the scale to take a reading. All 4 scales must be within 1/8 of an inch. I used newspaper to shim one of my scales up 1/4 of an inch--that's why I stood on the scale when measuring, to compact my shim material.

Check your tire pressure and bump it up to the hot pressure you run on the track. I use 2x6 wood planks as ramps to drive the car onto the front ramps then jack up the rear and lower it onto the rear scales. It's difficult to position all 4 scales so you can just drive up on all of them at the same time.

Before putting your car on the scales you need to power up the scales and zero them with no weight on them. Also double check that the scales are connected properly--you can really screw up your suspension settings if you have any of the scales connected improperly (i.e. front left and right swapped).

If you don't have adjustable end links on your anti-roll bars then leave them connected. If you do have adjustable end links then disconnect them for the corner balance. Once the corner balance is complete put someone in the driver seat and reconnect them so there's no preload on them.

Once you get the car up on the scales you'll need to roll the car back and forth a few inches several times, being careful not to push it off the scales, to unload the suspension (as the car is lowered onto the scales the tires will need to spread out to unbind the suspension). You will have to repeat this every time you lower the car onto the scales.

Note your ride heights and suspension changes to track your progress. When you adjust your coil overs to get the desired corner weights your ride height will change. Always document your current ride heights and your coil over changes each time you weigh and adjust. It's better to make many small changes than to try to balance your car in one big step. You can also estimate your car's center of gravity (CG) height by using this page: CG Height Calculator

On the Scales

If you prefer Microsoft Excel a Corner Weight spreadsheet is available for download here Corner_Balance.zip

This is a screen shot of the Excel Corner Balance spreadsheet:

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