Posted on September 22, 2017
The Fox body and the SN95 that followed it are great platforms
for building a fast car, but their stock suspensions leave a lot to be desired.
Fortunately, thanks to years of experimentation and development by parts
manufacturers and racers, it’s easy to set up your Mustang to handle on the
track and put down power at the drag strip.
How the Fox and SN95 Mustang Suspensions Work
The Fox platform was originally built for the Fairmont, a small family car with a simple suspension to keep costs down. When the platform was used for the Mustang, there were some minor changes to the position of the suspension components and frame to improve handling, but the basic design remained unchanged. When the Fox body was replaced with the SN95 in 1994, the suspension carried over, adding minor tweaks here and there to improve handling and steering input. In fact, the Fox and SN95 designs are close enough that many of the aftermarket parts we offer will work on both cars.
The front wheels are mounted on a modified MacPherson strut suspension. While this generally places the spring over the shock, in this application, the spring is mounted inboard on the A-arm, while the shock mounts to the steering knuckle and strut tower. This means the shock swivels with the steering knuckle when turning, which can alter the camber of the outside wheel in corners.
The rear end uses a four-link setup to position the axle. Due to the axle’s range of movement, these links can bind, causing non-linear forces to act on the suspension. That means the axle jumps around as the links bind and unbind, making handling unpredictable.
While this setup may be primitive, aftermarket manufacturers have had over three decades to find ways to remedy these issues, giving you several options when setting up your Mustang for the track, the drag strip and the street. While springs and struts may be first on your parts list, every part of the suspension system needs to be considered to get the best performance.
Stiffer springs react less to bumps, helping keep the wheels on the ground at the expense of ride comfort. Lowering springs are shorter than stock springs, lowering the car and the center of gravity. This reduces body roll and improves handling.
By controlling the flow of oil around and through the pistons inside the shocks, manufacturers can adjust their dampening effect for better handling and ride quality. Adjustable shocks allow this dampening to be tuned for better handling and to manage squat and rebound on launch.
Camber Caster Plates
By replacing the stock shock mounts with these plates, it’s possible to move the position of the top of the shock to alter the wheel position. Adding some caster can increase front end grip and tame camber changes in turns, while added adjustability allows the steering geometry to be restored after lowering the vehicle.
Aftermarket units are much stiffer than the stock stamped arms, reducing fore and aft deflection that can cause wheel hop. This is a great upgrade for street and race cars. Adjustable arms can be shortened or lengthened to change the angle of the arm, increasing thrust loads for more bite when launching and adding or removing loose roll steer for better handling. Setting up a four-link suspension this way can get complicated, so it’s generally best left for cars that will be used primarily on the track.
These bars link the left and right sides of the suspension, limiting suspension movement side-to-side. This reduces body roll on road courses and reduces axle twist during drag launches.
K-Members, Subframe Connectors and Torque Box Reinforcement Plates
The frame may not be the first thing that comes to mind when setting up your Mustang’s suspension, but it can absorb impact forces and release them just like a spring. However, unlike your suspension’s springs, there’s no shock to dampen the release of this energy, letting it interfere with the suspension. There’s a lot of flex in the Fox body, but it can be tamed by adding supports that stiffen the structure.
K-members are usually thought of as a component needed for engine swaps, but switching to an aftermarket unit can also add much needed strength to the front end to reduce twisting, keeping the front wheels planted through turns.
Subframe connectors link the front and rear subframes to create two complete frame rails, reducing twist in turns and when launching. Adding reinforcements to the torque box helps keep the lower control arms in position under load.
Improve Your Mustang’s Suspension with Help from Anderson Ford Motorsport
We’ve helped our customers build Mustangs for over three decades, so we know what it takes to get these cars to perform at the track and on the street. We carry the Ford Mustang performance parts you need, whether you’re looking to build a weekend cruiser, keep the wheels glued to the track, or shave tenths off your quarter mile.
All prices are in USD