The 1971 Boss 351 Mustang was the last of the true muscle cars of the era. It replaced both the Boss 302 and Boss 429 from the previous two years as the performance mustang in 1971. The Boss 351 Cleveland engine stocked 330 horsepower and featured a four-bolt man block, large port cylinder heads and valves, a solid lifter camshaft, an 11.7:1 compression ratio and aluminum valve covers. Also standard on the Boss 351 was Ram Air, 3.91:1 rear axle with Traction-Lok, Competition suspension, four-speed manual transmission, power front disc brakes, front spoiler, lower body side paint treatment and Boss 351 decals in place of the Mach 1 decals.
A chrome front bumper, instead of the rubber bumper found on the Mach 1, could also be found on the Boss 351. The black or argent paint, in the shape of a rectangle, covered most of the hood which differed from the Mach 1 hood scheme.
Standard wheel were 15 x 7 with trim rings/hubcaps. Optional were the chrome Magnum 500s, also measuring 15 x 7. Either way, tires were Goodyear F60x15 RWL.
The Boss 351 had much better low-end response than the previous Boss 302 and Boss 429 models, and its equal weight distribution made for better handling as well as better braking.
The Boss 351 replaced the previous Bosses and became the performance Mustang. The Boss 351 had very few options. There were 1,806 of these special cars made. It came only with the 351 Cleveland Boss engine.
Boss engine, rated at 330 hp @ 5400 rpm, and a 750 Ford 4300D carburetor. The engine had a compression ratio of 11.0 : 1 and drank premium fuel which was still cheap in the early ’70’s.
functional ram air on a hood that was mostly blacked out or painted an argent color. The hood also had twist locks as standard features.
4 speed manual transmission equipped with a competition Hurst shifter (an automatic was not offered).
competition suspension, with heavy duty front coil springs, and realr left springs, heavier front stabalizer bar and staggered rear shocks
Front power disc brakes
Front lower spoiler, MACH front grill and MACH1 lower body side paint. The body stripes were black or argent colored as well. On the rear of the car, the taillight panel and lower valance were either argent or black. A BOSS 351 Decal adorned the center of the deck lid. The front fenders declaired the car as a BOSS 351 and below the badge was the letters in non script “M U S T A N G”.
351 decals and tape treatment,
Chrome front bumper
The interior was the standard interior but you could upgrade to the interior decor group for a price. The speedometer was a 120 mph speedometer with an integrated trip odometer which was optional on other models. Also included (standard) with all Boss cars was the Instrument group with the Oil pressure, Alternator and Temperature gauges.
15×7 wheels and chrome trim rings held the F60x15 Goodyear polyglas GT tires. Optional wheels were the Magnum 500 wheels in either a chrome or argent plated finish.
Goodyear F60x15 RWL tires
Ford decided to pull out of racing after the 1970 model year. The Mustang handily won the 1907 Trans Am Series and so, there was no need to continue building the expensive, limited production Boss 302 engine. Still, Ford got a lot of mileage out of the Boss name and so, continued the concept into the 1971 model year.
The Boss 351 replaced both the Boss 302 and the Boss 429 Mustangs. Like previous Boss Mustangs, it was a complete package, with limited options. Standard was the 330 hp 351 Cleveland V-8 featuring a four bolt main block, large port cylinder heads and valves, a solid lifter camshaft, an 11.7:1 compression ratio and aluminum valve covers. Other standard features were Ram Air, 3.91:1 rear axle ratio with Traction Lok, four-speed manual transmission, Competition Suspension, power front disc brakes, front spoiler, the Mach 1 front grille and lower bodyside paint treatment, bodyside tape treatment and Boss 351 decals in place of the Mach 1 decals. The Boss 351, however, came with the standard chrome front bumper. The hood, also differed from the Mach 1s as the black or argent paint covered most of the hood.
Standard wheels on the Boss 351 were 15×7 with trim rings/hubcaps. Optional were the 15×7 chrome Magnum 500s. Tires in both cases were Goodyear F60x15 RWL Polyglas GTs.
Not a light car (3,750lbs), the Boss 351 could do the quarter mile in the high 13 second, low 14 second range. This equaled or surpassed the acceleration of other big-block equipped Mustangs (and other Pony cars as well) and its weight distribution made for better handling and braking. It also had much better low end response than the peaky Boss 302 and Boss 429 engines. A nice Mustang indeed.