Compromises have to be made...
Compromises have to be made on production cars to suit a wide variety of drivers, but that doesn't mean you can't get factory-engineered go-fast goodies. Ford Racing Performance Parts offers high-performance suspension components for all late-model Mustangs.
A torque arm is like an extra-long traction bar, as it lifts the chassis near the center of gravity, making available all of the car's sprung mass for transfer to the center of the rear axle, distributed evenly to both rear tires. It also controls rear axle brake torque and therefore increases antilift at the rear, making the rear brakes more effective.
According to Griggs Racing, "This has the effect of increasing rear traction while decreasing stopping distance by reducing forward weight transfer under braking. It does all this while at the same time making the car much more controllable and easier to drive hard in a corner, especially in corners on uneven surfaces or cresting hills, or when launching on poor surfaces, eliminating the 'white-knuckle ride,' even in the rain."
The 5-Link
Yet another way to improve your Mustang's handling is with the 5-Link designed by Steeda Autosports. The Steeda 5-Link suspension was bred through extensive track experience and testing, and is said to offer a roll-center reduction, positive lateral control, improved antisquat geometry, increased traction, and better dynamic stability. It consists of a Panhard bar, and two longer upper control arms that utilize different geometry to accomplish the same task as the stockers, but in a better manner.
Steeda's latest 5-Link 2 features improved compatibility with tailpipes, easier access to the differential for service, optional bolt-on installation, and compatibility with Steeda's adjustable rear sway bar and rear coilovers. Steeda claims the 5-Link has better antisquat geometry than a torque arm and less corner-exit understeer.
The 5-Link's upper and lower links work together to create an instant-center geometry, which moves in response to suspension loads. During acceleration the instant-center moves rearward to counter the effects of chassis squat. During braking, the instant-center moves forward in response to chassis lift, lengthening the side-view swing-arm to reduce the possibility of wheelhop that's likely to occur in a torque arm-equipped Mustang. In our own testing, we've noticed the 5-Link offers better ground clearance than a torque arm. We suggest you talk to people who run both systems and get their opinions. Also consider whether it's a Fox or SN-95 Mustang, your vehicle weight, tire choice, and general vehicle use before selecting one.
The Watt's Link
The Watt's link has been around for a long time, and it has most recently been seen beneath Saleen's '07 Saleen/Parnelli Jones Limited-Edition Mustang. This Pony was engineered with Saleen's Racecraft precision suspension, including the new race-derived Watt's link suspension.
The stock S197 Mustang suspension includes a Panhard rod and sway bar. While it's a good suspension system, it provides Mustangs with some unwanted characteristics associated with the suspension setup, according to Saleen. The biggest disadvantage the company sees with the stock setup is that as the suspension travels up and down, the axle travels in an arc and moves side to side in the chassis, which introduces unwanted lateral forces to the suspension.
"The Watt's link greatly improves the feel and handling of the car," says Bill Kreig, chassis systems supervisor for Saleen. On the track, it handles as if it has an independent rear suspen-sion, staying firmly planted through the corners. On the road, it produces a more stable and comfortable ride than the Panhard rod on high-speed/high-frequency roads, especially on California's bumpy freeways.