Why the first-gen straight-six Mustang deserves more love
The first-generation six-cylinder Mustang may not be the muscular powerhouse that pony cars evolved into, but it captures precisely what Ford originally intended the Mustang to be: a fun-to-drive sports car that wouldn’t break the bank. Marketed primarily to women and youth upon its release, the six-cylinder ’Stang satisfies the nagging craving for something sporty and reliable, with a practical amount of everyday cargo space. These days, however, the straight-six pony car is fast becoming a unicorn amid the popularity of both factory-original and V-8-swapped Mustangs.
If winning races at the dragstrip is your ultimate goal, not much will beat the dollar-to-power ratio of a small-block V-8. However, if you’re in the majority of enthusiast owners, you’re more likely to cruise around town with friends and family. If you’re really cool, you’ll opt to take your pony car on some scenic, long-distance road trips. That casual rhythm is where the straight-sixes shine, and their advantages are many.
Most importantly, these engines have been built since their first introduction in Ford’s 1906 Model K, so if you dare to stand out from the V-8 crowd, rest assured that these well-balanced six-cylinders are virtually bulletproof. When something does break, new replacement parts tend to be readily available and affordable. Used motors can be found for a few hundred bucks if the issue is catastrophic.
The straight-six in the ’66 is a pleasure to drive. It generates plenty of torquey power, yet runs smooth and can be tuned to get decent fuel economy. Cornering is a thrill: Instead of going nose-down into a turn like the V-8-powered brute, the nimble six-cylinder Mustang hugs the esses like they’re best friends.
The ’65–73 Mustang’s first six-cylinder was a 105-horsepower, 170-cubic-inch inline motor borrowed from the Falcon, but Ford’s wheels were turning even before the first car rolled off the line. Around four months after the Mustang’s introduction, Ford halted production of the 170-cu-in inline-six in favor of a 200-cubic-inch version. At the same time, the V-8 was upgraded from a 260 to the 289-cu-in iteration; the 302 came along in 1968 to keep up with tightening emissions standards.
The 1966 Mustang remains one of the most popular years—you’ll often see them on the road. The Standard Catalog of American Cars states that V-8 Mustangs outnumbered the inline-six production by 354,400 to 253,200 in ’66, making the six-cylinder less common than its more powerful counterpart. The hardtop model still holds the record as the best-selling Mustang of all time, accounting for nearly 500,000 of that year’s total sales. (For comparison, just over 173,500 units sold in 2000, the biggest sale year since 1980.) Towards the end of the first generation (’65–73), the Mustang physically grew larger, and its 1971 facelift lent it a fittingly more menacing look.
The Ford Mustang is the longest-surviving breed of classic American pony car—and the generation that started the line has aged well. Its aggressive styling and sharp, sloping lines make these first-generation examples appear low to the ground, like a predator on the prowl, whether in coupe, convertible, or fastback form; the straight-six-equipped cars look just as slick. Whether you’re all about that V-8 growl or want to experience the agile handling of the lighter six-cylinder, there is a Mustang waiting to give you the ride of your life.
I owned one of these in 1971. It was a bare bones car, with no power anything; it did have an AM radio.
The biggest weaknesses was not having a 4 speed transmission, I had to slip the clutch a lot when starting out. I got 21 mpg driving around Phoenix, with a 45 mph speed limit.