Basically just a Boss 302 with more cubes, the solid-lifter Boss 351 was a one-year wonder that hit hard on the tail end of the muscle car era. It was also one of the stoutest street Mustangs up to that point.
Rated 330 horsepower at 5800 rpm and 370 lb-ft of torque at 3400 rpm, it featured a special block, canted-valve Cleveland heads, a big-lift cam, 11.7:1 compression, an aluminum intake, and a 750-cfm carburetor. Its factory rev limiter was set at 6150 rpm. Just 1806 were built, all four-speed fastbacks.
Magazines recorded 5.8-second 0-to-60 runs and quarter-mile times as quick as 13.8 seconds, so it wasn’t quite as fast as the 375-hp 429 SCJ that year, but it was lighter and better balanced. It’s often called the best blend of the Boss 302 and Boss 429.
[Editor’s Note: This story originally appeared as part of the 25 Greatest Mustangs cover story in the July/August issue of Hagerty Drivers Club magazine. You can find the other entries here.]