Quote: Originally Posted by Sands
For strut type front suspensions, a front sway will actually work to minimize understeer. A bit counter intuitive, but it controls camber gain and will keep the front tires in better contact with the road. (Or at least that's the case with 3 and 5 series BMWs...)
Ummmm...yes and no.
A front sway bar will help keep the front end straight and stiff. A stiff rear will lose grip.
In RWD cars you need a stiffer front so that weight will stay on the rear tires as much as possible, which is where your rotation will originate. You also need that stiffer front to help keep the steering straight and lite.
In a FWD car, you don't have that power coming from the rear so you need it to be stiffer so it will lose grip and (as we mentioned before) help to rotate the car around the corner. You'll need a relatively soft front so it will flex around the corner, thus making the outer contact patch larger. A front sway bar actually hinders this.
I can't find the pictures a want to use to explain this, so I'll try it with words:
Say you're coming upon a hard right corner. In all cases, your contact patch will be at the left front tire under braking and turning in and it will move to your left rear tire under acceleration.
In order to come out of it well in a FWD car you need your rear stiff so that weight will transfer more to the left front than to any other tire. You'll need a relatively soft front so it will flex and allow more weight to transfer to the left front tire (this is one reason most FWD race cars don't even have a front swaybar). Upon acceleration, you want the weight at your left front to stay there, so you have a stiff rear so that it's harder for it to transfer to the back. If you have it set up properly, the right rear tire will pick up off the ground under braking. This will ultimately put the best contact patch on the front left tire.
In order to come out of it well in a RWD you'll need your contact patch to transfer more easily to the rear tires. You do this by having a stiff front and a slightly softer rear. If you do this properly, you'll pick up the right front tire under acceleration.
