The Ultimate Guide to Suspension and Handling Part 4: Reduce weight transfer

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On a car with McPherson struts the point is determined by drawing the line through the top strut mount bisecting the middle of the lower ball joint to the ground. The distance between this point on the ground, known to Coleman fans as the Dave Point and the center of the wheel forms a lever arm.  The lever arm increases the forces that the tire generates causing torque steer in front-wheel-drive and all-wheel-drive cars. It will also cause twitchiness and steering pull while braking especially on split coefficient of friction surfaces or road surfaces with uneven surfaces.

To minimize the change in scrub radius it’s important to try to increase wheel width to the inside of the car as well as the outside by closely paying attention to the wheel offset. This puts more rubber on the road and increases the track while maintaining the same scrub radius.

It’s not all about stance if it’s retarded.  Maxing out your track width and offset can reduce weight transfer and improve mechanical grip but taking it to an extreme is just plain dumb.  This probably doesn’t handle too well for obvious reasons.  I don’t think the owner cares though.

Increasing track width also changes the motion ratio of the suspension, which effectively reduces the suspension spring and anti-roll bar rates. Lastly, a very positive offset wheel puts a large strain on your wheel bearings, ball joints and steering linkage making them wear much faster. All of these are good reasons not to go crazy with this method of increasing track, hella flush, all about stance and whatever stupid trends be damned. A good rule of thumb is that it’s safe to use the largest wheels and tires you can stuff in your stock wheel wells doing no more than rolling the inner fender flange.

The Hella flush look can be performance enhancing if done correctly though!

A good guideline is to increase the track width and lower the car more on the end that that slides first in a corner. An understeering, nose-heavy front-wheel drive car can use more track width and a lower ride height in the front. A powerful, rear-engine car can be lower and have more track width in the rear. This play on physics will help in reducing weight transfer in both cases.

The Cyber EVO, the world’s fastest time attack car uses maximum offset and fills its wide body out to the limit.

In the next installments, we will discuss more basic mods that you can do to greatly improve handling, some of the common deadly sins of modifying your suspension and basic tips on suspension geometry.