Transforming a ’91 Coupe with MPS Expertise

Recently, MPS decided to put some of its inventory of 350,000 parts to use, along with that knowledge we mentioned, to demonstrate the sort of project you can build by using the company’s parts. MPS began with a worn-out ’91 coupe and decided to rebuild it using nothing but factory Ford parts, the same parts you can buy from MPS. The easiest way for MPS to accomplish this task was to select a donor vehicle from among its stock to contribute the bulk of its parts to the car, and while MPS could have selected another ’91, when finished, it would have had nothing more than a stock ’91 Mustang. So instead MPS chose an ’04 Mach 1 as a donor vehicle, and the quest to rebuild the coupe was on.

Upgrading the Suspension and Braking System

The Mach donated much of its front suspension to the Fox, beginning with its springs, struts and spindles, a conversion that made it possible to use five-lug wheels and brakes on the car. Thus, the Mach also gave up its twin-piston calipers and 13-inch rotors to give the lighter Fox-body coupe awesome braking power. The brake booster and master cylinder came from a ’96-’98 Cobra. The steering rack is a Mach piece. The wheels, however, are take-off parts from an ’06 Mustang GT, and the tires are 245/45ZR17 BFGoodrich g-Force Sport designs.

Enhancing the Rear Suspension

The rear Mach 1 suspension would have been fine, but it would also have been a lot like what this car originally came with, so the MPS guys decided to go one better. They pulled a complete IRS assembly from an ’03 Cobra and mated it to fit the ’91, instantly giving the car a huge bump in handling. The springs, shocks and brakes are all the ’03 Cobra pieces; the only change is the addition of 4.10 gears in the aluminum IRS centersection. The wheels and tires are identical to those in front.

Powering Up with Engine and Transmission Components

After finishing with the suspension, MPS continued to strip the Mach 1 donor car, removing just about everything under the hood for use in the coupe. Naturally, those donated parts include the 32-valve 4.6 DOHC engine. Even in stock form, the mod motor offers 305 hp and 320 lb-ft of torque, a pretty good upgrade from the 225 hp and 300 lb-ft present in a stock ’91 GT. The exhaust components, too, are factory pieces, as the pipes and mufflers are ’03 Cobra parts. The builders also moved the Mach’s 4R75W automatic transmission into the ’91, along with the aluminum radiator and expansion tank. With all these factory components in place, and left in their natural finishes, the installation looks like a factory effort—a car Ford could have built.

Refining the Body and Exterior

The body is stock, as there are few parts from a Mach 1 or any other SN95 car that would fit, or look good if they did fit. Instead, the builders just straightened the body panels, bringing it back to showroom condition, or perhaps better. The front and rear fascias are four-cylinder parts, and the taillights are LX pieces with smoked reverse lights. Dewayne Stiles applied the PPG Satin Silver paint, a color that suits the car well, especially with the satin-finish ’06 wheels.

Revamping the Interior

So, from the outside the car appears to be just another ’91 coupe, but the interior attempts no such trickery. The most obvious change is the addition of the ’03 Cobra seats, but that’s far from the only change. The steering wheel is an ’04 Mustang GT part, and the cruise-control switches are still functional. The stock dash contains the Mach’s instrument cluster, and Mach pedals replace the stock components. Dark charcoal carpet from an ’04 Mustang covers the floor, and a Mach 1 shift bezel surrounds the new shifter. Just ahead of that shifter is a modest, but sufficient, CD stereo deck from an ’01 V-6 Mustang.

The Final Result: A Factory-Level Build

MPS’ ’91 Mustang coupe shows just how good a Mustang can be using almost nothing but Ford parts, choosing the best components for the job and benefiting from years of parts-interchange and commonality. If you like the concept, all you need is a worn-out Mustang and MPS’ phone number or web address (mpsautosalvage.com). Just let MPS know what kind of parts you are looking for, and odds are it will have everything you need.