Automotive History: 50% Better – A Half-Baked History of Half Model Year Cars

(first posted 5/27/2020, updated 6/28/2023.)       Half-model year vehicles are an interesting historical oddity that you don’t see anymore. They briefly gained favor in the sixties as a way to distinguish mid-year model introduction and significant running changes, before falling out of favor in the early 1970s. Let’s take a look at this short-lived trend.

Before we get started, there is one thing that I should set straight right now: Legally, there is not now, nor has there ever been such a thing as a fractional model year. The serial numbering system of every manufacturer I’ve ever seen only supports whole number model years. Furthermore, the federal VIN system introduced in 1981 also only supports whole number model years. Every state that I know of requires a whole number model year on the vehicle title and registration.

That said, fractional model years have been employed over the years by enthusiasts and marketers to unofficially distinguish mid-model year introductions or significant mid-year running changes.

Perhaps the granddaddy of all half model year cars is the 1963½ Ford Galaxie. The 1960 Ford was a rare misfire in the history of full-size Ford models, and buyers stayed away in droves. Minor styling adjustments in 1961 and 1962 did little to improve the situation. Not only was it getting trounced in the showroom, but Ford was also getting trounced in NASCAR, due in no small part to the poor aerodynamics of its “Town Sedan” roof.

By 1963, Ford was desperate for a boost both on the track and in the showroom. Unwilling to wait until the following fall and the 1964 model year, Ford rolled out the “Sport Roof” in early 1963 as a “1963½” model, the ½ added to make it clear to the prospective buyers that this was a significant upgrade to the moribund 1963 Ford. Ford’s gamble paid off, and the Sport Roof was a hit both on the track and off, with 100,500 units sold in 1963, and boosting sales of full-size Fords by almost 20%, despite being available for just a partial model year.

Ford also gave the Falcon half model year treatment in 1963. In February of 1963, Ford introduced the Falcon Sprint as a 1963½ model. The Sprint is the first Falcon to sport a V8 engine, bucket seats, and a hardtop roof (which was also shared with the Futura coupe). In reality, the Sprint was a thinly disguised Mustang precursor, as its running gear would go on to underpin the Mustang in the following year. This really illustrates the power of styling and marketing: Despite being essentially the same car, the Mustang would go on to become an icon, while the Falcon Sprint would end up as little more than a historical footnote.

Speaking of the Mustang, perhaps the most famous half-model year car of all is the 1964½ Ford Mustang. As we all know, the Mustang was first launched to enormous fanfare in April of 1964. Technically, all the introductory Mustangs were 1965 models (they all bore VINs that started with “5” which at the time was how Ford indicated the model year).

Unlike the 1963½ Total Command Performance ad campaign, Ford never used the fractional 1964½ designation for these early Mustangs (at least not publicly). The 1964½ designation was made up by enthusiasts after the fact. In fact, early Mustang ads made no mention of a model year at all, just referring to the car as the “New Ford Mustang.” There were several running changes made during this extended 1965 model year production (about 16 months in total), enough to justify the informal ½ model year designation for the early production models.

1964 Ford Mustang

Rare early promotional photo showing “1964” Ford Mustang.


For starters, the Mustang was only available at launch in two body styles: A convertible and hardtop. The fastback wouldn’t come until later in the 1965 production run. Two V8 engine displacements were used in the 1964½ model: The 260 from the Falcon Sprint and the legendary 289. Production of the 260 ended after the 1964 model year, so the 289 became the Mustang’s sole V8 option midway in the 1965 production run. There are also other minor differences between the 1964½ and 1965 models, such as an alternator replacing the generator on the 1964½, and a variety of minor detail and trim changes.


Ford made one final dip to the fractional model year well in 1970, and once again it involves the Falcon. This time, however, the 1970½ Falcon would appear more out of necessity than for marketing purposes. Indeed, the 1970½ Falcon is a story of the misalignment between the model year and the calendar year more than anything else.

On January 1, 1970, new safety and crash requirements would go into effect in the US. Ford decided that the Falcon, having been on sale since 1960 and getting long in the tooth, was not worth the effort and expense of updating.

But there was a problem: Ford’s new compact car, the Maverick, was only available as a short-wheelbase coupe for 1970, leaving economy-minded looking for a four-door sedan with nothing to buy. So Ford produced a brief run of compact 1970 Falcons in the 1969 calendar year, before the new standards went into effect. A decontented Torino would serve as the “Falcon” for the remaining calendar year 1970 production, with a fraction added to the model year designation to differentiate the two Falcons. Interestingly, this decision was accompanied by a fair amount of boardroom drama, as Jeff Nelson documents in his history of the 1970½ Falcon.

There have been a few other famous half-model year cars (the 1970½ Camaro and the 1984½ Mustang, for example), but in these cases, the fractional designations have been applied by enthusiasts, and not by the manufacturer themselves.

Ford would make one last dip in the half model year well for the mid-cycle refresh of the Escort in 1985, but this would mark the last time that I know of that any manufacturer officially used a fractional model year in their advertisements.

It is easy to see why half-model year cars never really took off. While you do get cars in front of consumers sooner (and outside of the crowded fall launch season), it is basically double the work for your marketing department. You now need to design and produce twice as many brochures and ads, all of which now have half the usable shelf life. You can get most of the benefits of the early launch just by extending the introductory model year from 12 months to 18 (or more) months, which is exactly what all manufacturers do now when launching a vehicle early.


Related Reading

Curbside Classic: 1963 1/2 Ford Galaxie 500 XL – Something Old, Something New, Something Borrowed, Nothing Blue

Curbside Classic: 1963½ Ford Falcon Futura V8 – The Economy Compacts Enter The V8 Era

1970½ Ford Falcon: Mission Implausible