The late 1970s were bleak for fans of American muscle cars. The oil crisis and the strict emission standards rendered the powerful, big-block engines of the 1960s and 1970s obsolete and forced car makers to trade power for economy in just about every segment. This shift also affected the iconic Mustang, which in 1973 morphed into a rebodied Pinto that didn’t even offer a V8 at first.
It later received a 4.9-liter engine, but with an output of only 140 horsepower, it was a far-cry from the pre-1973 Mustangs. The suffering continued into the third-generation model, which in 1980 had a destroked, 4.2-liter V8 good for a miserable 118 horsepower. This made the new turbocharged, 2.3-liter four-cylinder, which generated 132 horses, the sole performance-oriented engine.
With the future seemingly built around smaller and more fuel-efficient units with forced induction, Ford wanted to bring more attention to the potential of the 2.3-liter. That’s when the McLaren M81, the rarest Mustang ever made, was born.
Development of the McLaren M81 Mustang
Developed around the same time the Special Vehicle Operations (SVO) division came to be, the M81 was the result of a collaboration between Ford’s newly revitalized Motorsport division and McLaren Engines of Livonia, Michigan. Its unique, wide-body exterior was inspired by IMSA race cars (mostly because the M81 itself went on to compete in the series), while the standard hood and front bumper were replaced by a fully function extracting unit and an aggressive chin spoiler. The beefed-up fenders covered wider-than-stock wheels and tires, while the active front and rear brake ducts kept the new components from overheating.
Inside, Ford kept many of the stock car’s features, but used Recaro LS bucket seats, a smaller, leather-wrapped steering wheel, a bespoke Stewart-Warner instrument cluster, and a then-approved SCCA roll cage.
The McLaren Mustang’s Engine
Under the hood of the car lurked a modified version of the 2.3-liter turbo-four from which McLaren Engines managed to extract 175 horsepower, 43 more than the standard model. Reports from the era claim that the boost control function was actually able to crank out around 190 horses, a remarkable figure for 1980. Torque was estimated at 145-pound-feet and delivered at only 3,000 rpm. The five-speed manual with its 3.45:1 final gear drive enabled the M81 McLaren to hit 60 mph from a standing start in 9.7 seconds and compete the quarter-mile at 17.37 seconds and 79.2 mph.
The McLaren Mustang’s Suspension
A revised chassis with fully adjustable Koni shocks, struts with higher-rate springs, and sway bars with tungsten bushings kept the coupe on its best behavior. Ford also fitted the M81 with BBS alloy wheels wrapped in Firestone tires, 10.6-inch front rotors with larger calipers borrowed from the V8 Mustang and 9-inch drums to the rear. The IMSA GTO-spec car received beefier brakes.
Production of the McLaren Mustang
Production of the McLaren M81 was initially scheduled at 250 units, including the prototype. However, only 10 additional cars were produced. Seven were finished in Bittersweet Orange, and one in Enduro, White, and Black. The reason for that was that Ford priced the M81 at $25,000 (the equivalent of nearly $80,000 in 2016), a sticker Mustang enthusiasts weren’t ready to pay in 1980.
With just 10 examples on the road, the McLaren M81 is the rarest Mustang ever made and a car most of us will probably never get to see in the metal. And even though the turbocharged four-cylinder didn’t catch on with Mustang enthusiasts, being discontinued for the fourth-generation pony, the M81 was proof that the Mustang didn’t need a V8 to perform well.
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