(Modified from original illustration in the Millikens' "Race Car Vehicle Dynamics")

I hope the schematic above is sufficiently clear. This suspension design is to be considered for those cars which lack chassis structure, rearward of the front attachment points for the suspension, with sufficient strength for attachment of a Panhard link.

This suspension has certain advantages over a conventional ladder bar suspension. Specifically, these two: There is no linkage bind while cornering, meaning the suspension is perfectly "streetable," and there is provision for complete dynamic cancellation of the driveshaft torque effect. In other words, if the rear tires are equally loaded initially, they will remain equally loaded throughout the run. This, in turn, means there will be no twisting of the front of the car.

That which I have labelled "link" replaces the Panhard link in its function. In other words, it is solely responsible for the lateral location of the rear axle assembly. This is the reason for its "Y" shape in plan view.

That which I have labelled "ladder" might not be a commercially available ladder bar, but it would be of the same general construction. Missing in the schematic are diagonal stringers which might be added for increased strength.

The front pivot points for both ladder and link will, in side view, be coincident. Distance forward to the pivot is not critical, though ground clearance will be lost as this distance is shortened.

While an antisquat value near 100% is desirable for a dragstrip car, wheel hop during braking might be a problem with an autocross or road course car with this high a value. The spreadsheet allows input of a lower value. There must be sufficient antisquat to provide cancellation, however.

The 2 "offset" values requested by the spreadsheet are in reference to the car's centerline in plan view. Ladder offset is positive to the right of the centerline. Link offset is positive to the left of the centerline. If the car's major roll axis is to be aligned with the car's centerline in plan view, the two offsets should have the same value. This would be more important for, say, an autocross car than it would be for a dragstrip car.

The spreadsheet provides the necessary setup information.