Nevertheless, a stiffer suspension does allow the chassis to respond more quickly to driver inputs, and in the accelerated world of racing, faster response to driver input can be the difference between clipping the apex or clipping the wall. There’s certainly room to stiffen up most cars without much if any downside (other than some loss of ride comfort), though as we’ve already explained, lowering the car’s center of gravity and widening its track is actually more effective at reducing weight transfer than reducing body roll is. In most cases, an unmodified road car is set up to be compliant and comfortable first and foremost, so body roll is an acceptable trade off. This ensures that the car handles the same in left and right turns, which is normally the goal with an autocross, time attack or road race car. Generally speaking, corner balancing is done to optimize cross weights, where the goal is to position 50% of the car’s weight over the front left and rear right tires, as well as across the front right and rear left tires. If you lower your car with coilovers, you also gain the advantage of being able to corner balance your car, plus you can alter the rake of the car (whether it sits higher or lower in the front than the rear). These allowed us to lower the ride height and center of gravity of the ASS2000 for better control over weight transfer while resetting suspension geometry back to more optimal angles. There are easy fixes for roll center and bump steer for most popular performance cars, though, like the Buddy Club roll center correcting ball joints and Blox bump steer correcting spacers we used on our S2000. So lowering a car’s center of gravity is a very useful tool (as is widening its track), but it does have a few unwanted side effect, since the suspension’s roll center and bump steer geometry changes for the worse and shock travel is reduced as well (unless you’re using a coilover system that allows ride height to be adjusted independent of shock stroke). Reducing a car’s ride height has the advantage of lowering its center of gravity, and this helps reduce weight transfer far more than limiting body roll does. For example, on a car with McPherson front struts like the E36 BMW above, too much body roll and thus suspension movement can result in positive camber on the loaded outside wheel and tire, which can cause the tire to roll over onto its shoulder and overuse that part of the contact patch, plus it can start to introduce bump steer and toe steer. In other words, body motion and the weight transfer that comes with it delays the chassis’ response to driver inputs, and this is both frustrating as a driver and in severe cases also does bad things to suspension geometry. But the primary downside to body roll is that it slows the “reflexes” of a vehicle, meaning it takes longer for the weight to transfer and settle such that the car is stable or has “taken a set” in racer-speak.
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