Ford Mustang Mach 1
The 1971 Mustang represented a radical departure from its predecessors. Under the direction of Bunkie Knudsen (poached from GM), the Mustang grew dramatically in every dimension — eight inches longer, six inches wider, and significantly heavier. The styling, penned by Larry Shinoda, was aggressive and polarizing, with a flat, NASA-ducted hood that seemed to go on forever and a low roofline that severely limited rear-seat headroom.
The Mach 1 was again the volume performance model, and for 1971, the standard engine was the 302 two-barrel (210 hp), though the car's true character emerged with the 351 Cleveland four-barrel. In 1971, the 351C-4V (M-code) produced 285 horsepower, but the real prize was the 351 HO (R-code) with its solid lifter cam, four-bolt mains, and 330 horsepower — a genuine street terror.
The biggest and most fearsome option was the 429 Cobra Jet and Super Cobra Jet — massive 429 cubic-inch V8s that turned the heavy Mustang into a straight-line missile. The 429 CJ was rated at 370 hp (net), and the SCJ added forged pistons and a mechanical lifter camshaft. These were among the last truly powerful engines offered in a production muscle car before emissions regulations took hold.
By 1972, the horsepower wars were ending. Compression ratios dropped, power ratings switched to the more honest SAE net standard, and the 351 CJ's official rating fell to 266 hp (though the actual output was similar to the previous year). The 429 was discontinued after 1971. By 1973, the Mach 1 was available only with the 302 2V or 351 2V, and the muscle car era was effectively over.
Long overlooked by collectors who preferred the smaller 1965-70 models, the 1971-73 Mach 1s have seen steadily rising values. The 1971 models with 351 HO or 429 power are now recognized as among the most potent Mustangs ever built.
These are large, heavy cars — confirm the body is straight, as collision damage can be hidden in the massive fenders. The 1971 351 HO (R-code) and 429 CJ/SCJ cars are the most valuable. The 351 Cleveland 4V (M-code) is the most desirable commonly available engine. Check for rust in the cowl, floor pans, and trunk. The flat, expansive hood is expensive to replace and difficult to find in good condition. Mach 1 graphics and decals are being reproduced but vary in quality.
The 1971 was the only year for the 429 CJ/SCJ in the Mustang. The 351 HO was available in 1971 only. By 1973, only two engines were available: 302 2V and 351 2V. Total production dropped each year: 36,499 (1971), 27,675 (1972), and 35,440 (1973). The 1973 models added federally mandated 5-mph bumpers.