Hotchkis Sway Bars - Curves And Sway

In stock trim the GTO has been affectionately compared to Shamu, according to Muscle Mustangs & Fast Fords Senior Technical Editor Steve Baur. The car is less than poised in the corners and didn't handle too well with the narrow 245/40R18 Dunlop Direzza DZ-101 tires. Hotchkis was one of the first aftermarket companies to address these issues. Its adjustable sway bars not only provide a range of stiffness settings, but they're also hollow, thereby reducing weight in spite of their increased size.

The factory front bar is 28 mm in diameter and weighs 18.5 pounds, while the Hotchkis bar is 33.5 mm (1.31 inches) and tips the scales at only 13.5 pounds. It has three adjustment points according to Hotchkis: 37-, 49-, or 63-percent stiffer than stock. The biggest difference comes in the rear bar. They both weigh in at 3.5 pounds, but the 19mm Hotchkis bar has four adjustments that are 50-, 76-, 111-, and 156-percent stiffer than the stock 16mm bar.

Precision Motosports of Florida installed the Hotchkis products, making short work of a seemingly arduous task. It requires a front and rear cradle alignment, as well as a four-wheel alignment, something that is highly suggested even on the softer stock suspension, which tends to come out of alignment after regular street duty.

For the Hotchkis bars, our testing facility was the Gainesville Raceway. In addition to it's world-class dragstrip, the facility also has a road course that allows for repeated, consistent testing. Our driving impressions were derived from the road course, and our lateral g numbers were found on the 200-foot skidpad.

With the new bars under the car, the on-the-road feeling was immediately improved, so we were excited to see how much more performance we could get with these bars through tuning at the track. To begin with, they were adjusted to their loosest setting, 1 and 1. Tire pressure was raised to 40 psi to prevent the tire from rolling over, and we took our laps around the skidpad and the road course. The improvement was noticeable, but not dramatic compared to stock. The GTO uexhibited a tendency to understeer.

We jumped the rear bar up to the next setting, No. 3. After taking a few hard corners, things felt right on the road course. The GTO felt balanced, like the only thing holding it back was the tires. We settled in for the skidpad, knowing these had the potential to be our best numbers. The results speak for themselves, as the recorded grip was the best of the testing.

Despite this, we tried stepping the rear bar up to its stiffest setting, No. 4, but the back end seemd too stiff and went into oversteer too early. With a softer tire, the stiffer settings may prove to be ideal. The front bar wasn't put beyond No. 2 because of rumors of the factory endlinks bending.

Conclusion After the day was through, we concluded that the improvements seen and felt with these sway bars are substantial. You would be hard-pressed to find a larger improvement from a single upgrade other than tires, but tires won't reduce the body roll. On our GTO, we found setting No. 2 up front and 3 out back were the clear victors, from the driver's seat and in the numbers, as they improved vehicle control dramatically.

Notes:
1. While these settings are stiffer than stock, the Goat didn't feel very controlled. There was noticable lean, especially in the front.
2. These settings certainly were felt in the back of the car, but the front tended to wander in transitioning corners around the road course.
3. These settings felt very confident and were what kept when leaving Precision. It did, however, feel a little tense when brought to the edge of grip.
4. At 2 up front and 3 out back, the GTO felt very balanced on our 300-wear-rating street tires. Any understeer was very easy to overcome with the throttle, and the car was extremely easy to drive on the edge of control around the skidpad, unlike Run 3.