When Ford pulled out of racing in the summer of 1970, there was no longer a need for the race-inspired Boss 302 Mustang, which homologated a special Cleveland-head small-block for Trans Am competition. That opened the door for the Boss 351, an engine that put 49 additional cubic-inches under the large intake ports for more horsepower and increased tractability on the street. Based on the 4-barrel version of the 351 Cleveland, the midsize engine was transformed into a Boss by utilizing a 4-bolt main-bearing block, solid-lifter camshaft and aluminum intake manifold topped by an Autolite 4-barrel carburetor. Packaged into the restyled 1971 Mustang SportsRoof with Competition Suspension, 15-inch wheels and tires, 4-speed with Hurst shifter, 3.91 gears in a 9-inch Traction-Lok rear axle and functional Ram Air hood, the Boss 351 was capable of high 13-second quarter-mile times with handling to match. Visually, the Boss 351 was identified by its front chin spoiler along with two-tone treatment for the hood, lower body sides, hockey-stick side decals and rear panel. Offered for one year only, just 1,806 Boss 351s were produced in 1971. Rotisserie restored, this light Pewter Metallic is a single year only paint color, is equipped with its matching-numbers 351/330 HP engine, which is still equipped with its original blue-tag 01ZFZA Autolite carburetor and D12F-12127-DB dual-point distributor. The 4-speed transmission waits earnestly for the Hurst T-handle shifter to be rowed through the gears. Well-equipped, the Boss 351 is optioned with the black Décor interior with knitted vinyl bucket seats, rear spoiler, Sport-deck (fold-down) rear seat and power front disc brakes. The Boss is also equipped with its original space-saver spare tire in the trunk and optional 15-inch Magnum 500 wheels with Firestone Wide Oval tires. The sale of this nice Boss 351 includes the original build sheet and Marti Report. This is truly a very important car especially in the Muscle car world.