Mustang Restomod Guide : Suspension
Want to upgrade your vintage Mustang's suspension? In today's restomod market, you can go from mild to wild.
Braced for Action
From the factory, '65-'70 Mustangs destined for the American market came with thin metal braces to connect the shock towers to the cowl area. When Carroll Shelby began looking for ways to strengthen the car's front end for his GT350s, he discovered that Ford installed a heavier-duty, one-piece brace on exported Mustangs. For Shelby, it was a quick-and-easy modification available over-the-counter at Ford parts departments.
The export brace, as it became known, is still a great modification for vintage Mustangs. Available from most Mustang parts vendors, the brace is a direct replacement for the production ones. The shock towers on most '65-'70 Mustangs have settled inward, meaning you may need to spread them to get the export brace to fit. In most cases, the car can be supported on jacks where the lower control arms connect to the shock towers. The resulting droop can spread the towers apart enough to install the brace. In extreme cases, a hydraulic ram may be needed to push the towers apart.
Although coilover suspensions are the rage these days, upgrading the factory suspension is a more viable and less expensive way to achieve improved handling for many vintage Mustang owners. The Grab-A-Trak suspension kit from Mustangs Plus is ideal for performance-oriented Mustangs that see frequent street use. Designed for a firmer-than-stock ride and flatter handling, the Grab-A-Trak kit includes 620-pound front coil springs; four-leaf, standard-eye leaf springs; a 1-inch front sway bar; a 3/4-inch rear sway bar; performance shocks; new leaf-spring shackles with rubber bushings; and polyurethane coil-spring insulators, sway-bar end links, and sway-bar frame bushings. Several upgrades to the standard kit are available, including mid- or reverse-eye leaf springs and a larger 1-1/8-inch front sway bar. With the standard Grab-A-Trak suspension, expect the rear end to sit at the stock height with a 1-inch drop at the front.
Due to front suspension design, every vintage Mustang has some degree of bumpsteer. It becomes more noticeable when the car is lowered or modified with suspension improvements that make the vehicle more responsive to steering input. When experienced, the car twitches or darts around on bumpy or undulating roads. It can also be twitchy during braking, pulling from one side to the other.
Bumpsteer can be eliminated by ensuring the tie-rod pivot point matches the travel of the spindle with a bumpsteer corrector kit from Pro-Motorsports Engineering. A spacer block, secured by a strap, "lowers" the tie rod so it's more in line with the lower control arm. With the angle of the tie rod and lower control arm almost identical, bumpsteer is essentially eliminated.
The Street Bandit kits from National Parts Depot contain all the ingredients for balanced handling at an affordable price. Available for '65-'66, '67-'70, '67-'70 big-block, and '71-'73 Mustangs, each component has been matched specifically to the vehicle for neutral balance and improved cornering without a stiff ride. The kits include a set of KYB Gas-A-Just shocks, a 1-inch front sway bar, a 3/4-inch rear sway bar, lowering coil springs, rear-end lowering blocks, and polyurethane sway-bar end-link bushings. NPD says maximum stability is obtained with new rear leaf springs, available separately.
No More Sway
Even with a fat sway bar up front, stiffer springs, and big tires, vintage Mustangs can use more help with handling. When roll control is out of control, add an adjustable rear sway bar from Scott Drake Mustang Parts. Measuring 3/4 inch in diameter, the Scott Drake bar (PN C5ZZ-5486-ADJ) provides adjustability for dialing in maximum handling. It's powdercoated to prevent corrosion and comes with polyurethane bushings. Scott Drake also offers a nonadjustable bar for '65-'66 and '67-'70 Mustangs.
They may be old-school, but the Traction Master underride traction bars from Tony Branda Mustang & Shelby Parts work as well today as they did 40 years ago. Vintage-Mustang leaf springs tend to twist or "wrap up" with hard acceleration, leading to wheelhop that can be violent enough to break axles and snap springs. The bars provide new attachment points for the rear axle, so it's not held in place solely by the leaf springs. Once installed, they also serve as trailing arms to solidly locate the axle in relation to the car. Installation is easy-the underride bars basically bolt-in with the exception of some welding that's required to attach the front mounting bracket. Look for PN TM1068 for '65-'66 Mustangs and PN TM1069 for '67-'73s.