Upgrading the 3rd link suspension arm in an S197 Mustangs is far more important than just to reduce wheel hop. Picking the right one will greatly affect the car’s handling and rear grip (and we all know Mustangs need rear grip). To improve the performance of our budget track car, we install the best 3rd Link on the market, from Roush Performance.
The S197 Mustang has a 3-link rear suspension with a Panhard Bar that is transversely mounted and locates the solid axle laterally when cornering. The 3 longitudinal links consist of 2 lower control arms and the upper “3rd Link”.
The 3rd Link suspension arm plays a crucial role in how the S197 Mustang handles and its ability to put power to the ground when exiting corners. Aftermarket links are often marketed simply to reduce “wheel hop”, but it’s far more important that just that.
Going with bushings that are too stiff will reduce rear grip and performance on a road course and increase NVH, transmitting unwanted vibrations and harmonics into the cabin in ways that adding Dynamat cannot solve. (Been there, and won’t be making that mistake again).
Roush Performance’s 3rd Link is hands down the best option for all S197s that are driven on the street, and 99.9% of the cars that are taken to the track. It has also won more professional races in the IMSA/Grand-Am GS class than any other 3rd Link on the market.
Getting power to the ground was the key competitive advantage that Jack Roush Jr. and I had when competing with the S197 chassis (from the FR500C to the BOSS 302R) in the IMSA/Grand-Am GS class. This was no easy task since these endurance racing cars weighed over 3,600lbs with driver, produced over 450 horsepower, and competed on skinny 275-width spec tires.
We tested over 10 different 3rd links from off the shelf products to our own designs. We quickly learned that having zero compliance from a spherical bearing or solid (and even perforated) polyurethane 3rd link transmits torque too quickly, shocking the tires and breaking traction. This reduces rear grip and makes it more difficult to accelerate out of a corner.
The Roush Performance 3rd link consistently out-performed everything we tested, by a noticeable margin. Lap times improved, tire wear was reduced, and the car was easier to drive.
The Roush 3rd link has a small, hard durometer rubber bushing that dampens the shock from the rear-end and greatly increases rear grip over a spherical or polyurethane bushing. The Roush link is significantly stiffer than stock and eliminates wheel hop and unwanted movement and geometry changes.
This was a competitive advantage that we held over other Mustangs and enabled us to exit a corner with more grip and acceleration than any other car in the field. This benefit, without increasing NVH, increases rear grip and performance that is much needed in almost every S197 application.
The stamped steel link has a metal strap that wraps around the bushing and is welded to the backside of the arm. This prevents the arm from cracking or ‘unwrapping’ from all of the torque it receives from acceleration and deceleration compressive and tension forces. At Roush, we raced with this link for years without ever having to service or replace the arm or bushing. They are quite durable.
Page 1 – Problem & Roush 3rd Link
Page 2 – Remove OEM 3rd Link
Page 3 – Install Roush 3rd Link & Conclusion