Muscle Mustangs & Fast FordsHow To Chassis Suspension
Ford Mustang Suspension Guide - Suspension Dimensions - Tech
MM&FF Takes The Mystery Out Of Your Mustang's Suspension.
When you get in your car and head down the road or the nearest slice of racing asphalt, you often take for granted the engineering, research, and development that goes into the components that keep your ride planted to the pavement. When dealing with your Mustang or some other fast Ford, you can be sure the Blue Oval has gone through great expense to give you the best suspension for each application and price point.
Because Ford (along with every other manufacturer) must design its suspension systems for all-around use (comfort, performance, and longevity), compromises are usually made, and for us enthusiasts, those are most notable in the lack of cornering prowess. Luckily, the aftermarket is rich with high-performance suspension components that swing the balance of focus to optimal handling, whether they're upgraded, stock-style replacements or completely reengineered components.
Ask a variety of people what "handling" means and you'll get as many different answers. Nonenthusiasts may consider great handling to be a comfortable ride that absorbs the bumps and imperfections in the road and minimizes NVH (noise, vibration and harshness). Most performance enthusiasts, however, think handling means having great road-holding or grip capabili-ties. But before you can improve handling, you should know what affects it and what to expect from the changes you make to the car's suspen-sion and chassis.
Like the term "handling," the words "chassis" and "suspension" are often interchanged, but they are, in fact, totally different parts of the car. Simply put, the chassis is the frame or major structure to which all of the suspension parts are bolted, bonded, or otherwise secured. For instance, some cars and trucks have an actual frame to which the body is bolted. Meanwhile, vehicles like the Mustang have a unibody chassis structure, where the body and frame are a single structure, and the suspension is fixed to it. For the scope of this article, we'll be talking about your Mustang's chassis and suspension system and what aftermarket components are available to improve its lateral grip, ride quality, and safety.
All '79-'04 Mustangs feature a modified MacPherson strut front suspension incorporating struts, lower A-arms, and coil springs mounted between the A-arms and the K-member, which is bolted to the unibody. The system is enhanced by an antiroll bar. The front lower A-arms use rubber bushings to reduce NVH, but they can also deflect during aggressive cornering maneuvers.
Griggs Racing notes that this, as well as other compromises found in the front suspension, are made abundantly clear when driving a car with the rear suspension corrected and the front suspension is stock. According to Griggs, "Ford built the Mustang with generous steering axis (kingpin) inclination, which requires equal amounts of caster to keep the tires flat to the ground when turned. Unfortunately, Ford gave the Mustang only minimal caster-a condition we can change with caster plates and a redesigned K-member."
Also at the front, Ford's tall ride height comes into play. Lowering the entire car drops the center of gravity, but causes the front suspension geometry to lower the front roll center well below ground level. Lowering the rear roll center with a Panhard bar or Watts link in the rear suspension helps this condition, of course, but Griggs Racing says you also want to raise the front roll center, which can be accomplished by relocating the points where the front suspension attaches to the chassis. Moving the suspension pickup points is done by redesigning the K-member.