Contour Enthusiasts Group Archives Forums General Autocross and Open Track sway bars

what size combo front and rear sway bars should be used for optimal handling for auto X. dont want oversteer. should the back just be upgraded and leave the front. need input.

If you put a larger rear sway bar on, you will have MORE oversteer. The car is neutral now. Either do both or get a fully integrated kit with springs and sway bars and bushings etc. You can't make any change without leaving stock class though...well you can change front bars, but that just gives you more understeer unless you get a smaller front one like the SVT.

So changing the rear bar without changing anything else will not help in the handeling dept.

I think I was saying what Terry Haines has pointed out. If you take the parts bin approach, and throw dichotomous parts together you end up with handling worse than when you started out.

A bigger rear sway bar will reduce understeer and provide more oversteer. But Jackie Stewart and some other famous guy helped design the handling in our cars and made it pretty darn neutral to begin with. Too much oversteer makes you unstable at speed and more likely to swap ends in steady state curves and even more so in slalom-like transitional maneuvers.

I would have told him to get Terry's/L8apex's aussie bar but he said he did not WANT more oversteer. Ideally you would want about the same handling characteristics we already have but at a higher limit of adhesion. That's why many autocrossers just buy sticky autocross tires. The tires leave the same overall balance but increase the lateral g, acceleration and braking capability. And if you get Koni or other adjustable shocks, you can fine tune with them as Eric Ford pointed out in his thread about the Peru National Tour event. Stiffer shock settings in front decrease oversteer, stiffer settings in the rear decrease understeer.

Just as a counterpoint though:

This car, like any other, is tuned from the factory to be biased toward understeer, which is considered the less frightening option for most drivers--that is, the lowest common denominator.

SVT took the approach, rather than plus-sizing the rear, of downsizing the front bar to tune out a teency bit of that understeer.

I would say that on an SE, a bigger rear bar is a fairly conservative approach, as it should reduce lean in the corners, and tune out some understeer, without affecting overall ride quality in "level cruise." Aren't there lots of SVT's running the Aussi bar? If anyone's going to have oversteer problems, it should be them. On an SE, it would be less of a problem, due to the larger front bar. Or if there's still a concern, how about the BAT bar?

Obviously, you can go too stiff on a rear bar, but I think (though I don't know from experience) the the bars available to us offer a small enough shift in under/over balance not to be dangerous.

Of course, I agree that tires ought to be number one.

Well,

I'm going to try the Aussie bar this weekend at an AutoX event.

I believe it dials in a mild amount of oversteer. However, I will probably begin to run with about 1/2 tank of fuel instead of a full tank. (I was trying to get the car to rotate.)

As long as I can continue to control the car well, dropping about 50# of fuel, and perhaps a lighter battery being located in the rear (See my Dyna-Batt post in General Mods), I might shave off another a tenth or so. And I still believe seat time and so more drivers training will do wonders for me.

(Of course, I can put the driver on a weight reduction program as well, but gosh that's harder, LOL.)

Anyway, I'm going to try it out. I still have the stock bar I can return in about 60 to 90 minutes of work, including the prep and clean up, so you can experiment with this relatively cheaply.

I'm sure some mod crazed member would buy my Aussie bar, 'specially since you have to have 30 or so folks in a group to order them.

What I've experienced on the exit ramps is that the back "feels" like it wants to come around. Yet it doesn't (YET!)

I guess Sunday will tell regarding slaloms and such. I'll give it a few events and then decide.

FWIW,

TB

hey thanks for the input guys. i appreciate it.

From my experience on the track, the SVT is not neutral, it has way too much understeer. Though it could be just the relatively crappy tires I had on at the time..