By alley - Jul 19, 2017, 1:33 PM ET

Autocross Handling Secrets: Swaybar tuning

As we discussed in

the first part of our Autocross Handling Secrets series

, tuning a car's performance via swaybars is essential in SCCA autocross competition where the rules are limited. In that story, we learned what swaybars do on different cars – now it's time to go deeper. What if the rules for your class allow for alternate springs in addition to swaybars, or what if you want a more custom swaybar setup?

"You are trying to use the swaybar more as balance for steady state cornering in a car where you can do more modifications, where in a stock-based car it may be the only thing you can do," explains suspension guru Guy Ankeny, who works in the Damper Works division of FR Sport. "You are trying to get power down, or keep the platform more level so you can maximize the grip you have on the tires."

There is, however, no such thing as a free lunch. By its nature, a swaybar takes some of the "independent" out of independent suspension. "If one tire hits something, it really affects the other one," says Ankeny. "Sometimes you have to run a big bar, but there are drawbacks to it – you don't get something for nothing."

Most popular vehicles will have plenty of off-the-shelf swaybars available, but others are not so lucky. The good news is that with a little engineering you can often come up with the perfect match via a custom-built swaybar. This is not nearly as frightening or costly as it may sound.

"I look at a little bit of everything – the spring rates that the car has, what the motion ratio would be, and what the car is being used for," Ankeny explains when designing a one-off swaybar setup. "If you are using Hoosiers versus a 200 tread wear tire, you're going to experience more body lean, so you are trying to counteract that."

When it comes time to dialing in your swaybar, it's good practice to make a change that will actually make a difference.

"If I had to pick something, I would generally go bigger, and then come back down to earth," says Ankey about trying out a new swaybar setup. "In other words, make a big enough change where you feel it. The more you use them, the more you will understand them.

"A lot of times we say, 'It's just oversteering or pushing this much, so I'm just going to make a little change,'" he continues. "Well, you can make a tiny change and sometimes you can hardly tell that there is a difference – you have to make enough of a change that you can tell you are going in the correct direction."

Along those lines, Ankeny emphasizes how important it is that any adjustable swaybar be easy to adjust. "Having a bar that is adjustable is important, and the easier it is to adjust is even more important," he explains. "Having a bar that takes half an hour to adjust is almost a waste of time, because you can't test it back to back."

The most common adjustable swaybars feature pre-drilled holes that allow you to independently adjust each side, altering its stiffness by a few percent – but there are other options as well. "The blade bar is the easiest," says Ankeny. "It has a great range of adjustment, and is so quick to adjust. Some of the ones I've built can be adjusted in less than 15 seconds, and that is key when trying to adjust cars in a quick period of time."

The speedway style, Ankeny says, is nice, but he has a preference on how those are adjusted. "You can get arms that are pre-drilled or even drill your own, but I like slotting it the best. Slotting it makes it easy to adjust."

No matter what you decide for a swaybar, don't overlook the rest of the system. Items like adjustable end links can help even original equipment swaybars perform better, as they allow you to tune out preload.

"It's basic common sense on those," says Ankeny. "Making sure the bar does not have preload in it – it makes the car more consistent, easy to drive, and offers repeatable results."