Driving a car that is a “leaner” is no fun. You wonder if the door handles are going to scrape off negotiating a tight corner. Even if your car has stiff suspension a properly sized anti-roll or sway bar will improve its stance in a corner. That is because the bar adds spring rate as the vehicle tries to roll. On the straight away or when not maneuvering the spring rate is not there. To add the additional spring rate needed to stay relatively flat in a corner would mean a really stiff, uncomfortable ride.
How is it possible to just selectively add spring rate? The diagram shows the ingeniousness of a sway bar in that it is a torsion spring which is tied to the suspension and body through the sway bars bushing and the vehicles moveable suspension parts like the lower a-arm in front or the differential housing (non-independent cars) in the rear. The net result is that it is affective only when the vehicle tries to lean. Consider it spring on demand. The more the vehicle tries to lean the more it resists leaning. On the other hand when you go over a bump that is across the entire road the bar rotates in its bushing with no addition of spring rate. This directional bias makes it perfect for reducing body roll.
Body roll is also connected to whether a car has bad habits like oversteer previously discussed. That’s because the more the body rolls the more is messes with the steering geometry (mostly camber) causing the car to do things you would not expect when you corner. We have shown the front suspension but the rear can use the same treatment only with a much smaller bar diameter since front engine vehicles have so much more mass to affect the front suspension.
How Much is Too Much?
With this knowledge you would think you would want to bolt on the biggest, baddest sway bar you could find. Not a good idea, you see the suspension needs to be able to react to the irregular surface of the road or track in a straightaway and in a corner. If you put a huge sway bar on when you start to corner the spring rate (stiffness) of the suspension will go way up disproportionately to the weight of the vehicle. The suspension becomes so rigid that it can not do its job of properly following the surface to keep the maximum contact patch (tire footprint) against the surface. You will loose traction, reduce the maximum speed you can take the corner, and it will ride just like a go-kart when you hit a bump in a corner – like it had no suspension at all – ouch! From this you can see that properly sizing the sway bar is essential if you expect to improve the handling, reduce body roll and retain the ride characteristics.
If you are a Corvette C2 or C3 owner SpeedDirect has a tailored package that matches springs, shocks and sway bars for an optimal combination depending on three driving preferences:
Shark Bite TM Cruiser TM Suspension Stage Kit – A smooth ride that handles great.
Shark Bite TM Instigator TM Suspension Stage Kit – Firmer ride, improved handling.
Shark Bite TM Nemesis TM Suspension Stage Kit – Solid ride, maximum handling.
One of these is right for your driving preference and style.