Rare Rides: The 1966 Shelby GT350 Convertible

If I were to query you as to what your Holy Grail vintage muscle cars are, I could probably guess what many of you would say. The 1969 Chevrolet COPO Camaro ZL-1; the 1970 and ’71 Plymouth Hemicuda convertibles; the 1971 Pontiac GTO Judge ragtop

It’s easy to see why you’d pick them, since they represent the rarest apex predators turned out by two of the Big Three manufacturers – General Motors and Chrysler. Their transcendent looks and histories of stoplight racing glory are also undeniable and have captured the imagination of vintage car aficionados the world over.

But what if you’re a Ford guy? Well, of course, there’s the Boss 429, the Mach I, and a host of other FoMoCo cars with big-block power in them which could boast of the same allure.

But if you’re like me, your choice would have to have come from the stable of Carroll Shelby and his merry gang of gearheads at Shelby American. The enhanced muscle and performance they breathed into run-of-the-mill Mustangs most assuredly make them the most desirable Fords ever made.

If you’re still with me up to this point, then there can only really be one model of Shelby/Ford monster that you’d choose – the rarest Shelby of them all – the 1966 GT350 convertible. And if so, then I’ve got some good news for you: it’s the subject of this month’s Rare Rides!

The 1966 Shelby GT350 convertible. (Photo courtesy of The Coolector.)

The working relationship between Carroll Shelby and the Ford Motor Company is the stuff of automotive lore and had its origins in rectifying an unkept promise by legendary Ford executive, Lee Iacocca.

Then Vice-President of the company, Iacocca had stipulated at the Mustang launch in April of 1964, the forthcoming car would be a true high-performance vehicle, capable of both street and racing use.

Lee Iacocca, second from right, at the Mustang launch in April of 1964. (Photo courtesy of Ford Motor Company.)

In actuality though, the first-generation car ended up lacking the power and handling prowess to qualify as anything more than a spirited pony car. In order to fulfill the car’s original purpose, Iacocca was forced to seek out a specialty contractor that could modify the car and transform it into a legitimate performance vehicle.

Carroll Shelby in the early 1960s, behind the wheel of one of his famed Cobras. (Photo courtesy of The New York Times.)

Carroll Shelby already had, by this time, an association with Ford via his use of Ford 260, 289, and 427 cubic-inch engines in his Cobra roadsters, and through having helped to develop the GT40 race car that would later go on to beat Ferrari at Le Mans in 1966. As such, he and his company, Shelby American, was the obvious choice for Iacocca.

Mustang Fastbacks being modified at the Shelby American shop in Venice, California. (Photo courtesy of Mustang Monthly.)

A deal was struck, and in August of 1964, the first 110 standard Mustang Fastbacks arrived at the Shelby American garage on Princeton Street in Venice, California to be metamorphosed into beasts with claws and teeth.

The first generation 1965 Shelby Mustang, given the random moniker “GT350” for the number of feet between the production and race shops at Shelby American, was bestowed with a 289 cubic-inch K-Code V8 engine. By virtue of a Holley four-barrel 715 cfm carburetor, Cobra Hi-Rise manifold, cast-aluminum valve covers and oil sump, a larger radiator, and tubular Tri-Y exhaust headers feeding short side pipes, Shelby bumped the Mustang’s horsepower to a stated, and vastly underrated, 306 ponies. Performance was a 0-60 mph time of 6.8 seconds, the quarter-mile tripped in 15 flat at 91 mph, and a top speed of 135 mph.

The business end of the ’65 GT350. (Photo courtesy of MustangForums.)

A four-speed, Borg-Warner T10 all-synchro transmission with close ratios housed in an aluminum case and tail shaft, and a ratchet-type limited-slip differential were standard equipment.

Other Shelby goodies included a quick-ratio steering rack, oil coolers for the differential, semi-elliptical leaf springs, a beefier rear axle from the Ford Galaxie, more robust anti-sway bars, Koni adjustable shock absorbers, Kelsey-Hayes front disc brakes, and a trunk-mounted battery for better weight distribution.

The cars featured a number of exterior modifications as well. Amongst them was a fiberglass hood with functional scoop and hold-down pins, a revised grille, and 15-inch Kelsey-Hayes mag wheels shod with Goodyear high-performance Blue Dot tires.

The 1965 Shelby GT350. (Photo courtesy of Mecum Auctions.)

1965 GT350s were only offered in Wimbledon White with Guardsman Blue rocker panel stipes and call-out. Roughly thirty percent of the cars that left the Shelby garage came outfitted with the matching Le Mans style racing stripes across the top that was, contrary to common belief, an extra-cost option.

Inside the GT350, there was a dash-mounted tachometer and oil pressure pod, Shelby badging on the simulated wood-rimmed steering wheel, 3-inch competition seat belts, and, as a nod to the seriousness of its racing aspirations, no rear seat.

For those who craved an even higher echelon of performance, an “R” model was also produced for 1965, which complied with SCCA racing specifications and was, therefore, ready to race out of the box. Horsepower was upped to a listed 360, thanks to heavily modified heads.

The 1965 GT350R. Note the unique front apron. (Photo courtesy of Mecum Auctions.)

Maximum attention was paid to weight savings in the GT350Rs which included the removal of the heater, defroster, sound insulation, upholstery, headliner, rear quarter windows, and vents. Lightweight seats, a stripped instrument panel, plastic windows, a roll cage, and a unique fiberglass front apron completed the package.

The Shelby GT350 made its public debut on January 27, 1965. In total, 562 GT350s were built that year with only 34 of those being R-spec cars.

The 1966 Shelby GT350 Fastback. (Photo courtesy of autoevolution.com.)

1966 was largely a continuation year for the GT350, with no major design or drivetrain changes to the basic car. That is not to say though that there wasn’t a host of smaller standard updates and differences, and a few new options as well.

Mechanically, the battery was no longer located in the trunk on non-racing models, and the exhaust pipes were extended to the rear of the car for a less cacophonous, more street-friendly exhaust note. A bolt-on Paxton supercharger that boosted power to close on 400 horsepower and a SelectShift 3-speed slushbox were now offered as expensive optional equipment.

The engine was the same spec as the 1965 version, but there were small changes to the aesthetic appearance of some of the components, including a different finish to the valve covers and a revised casting of the intake manifold.

Comparing the ’65 (background) and the ’66. Note the latter’s quarter panel windows, side scoops and rear-exiting exhausts. (Photo courtesy of diyford.com.)

The exterior of the ’66 had a trio of noticeable differences and a bevy of small ones.

The three big changes were the addition of functional, fiberglass scoops on the flanks ahead of the rear wheels that fed cool air to the rear brakes, a variety of styles of 14-inch wheels instead of 15s to provide better fender clearance and new Plexiglass quarter-panel windows that replaced the vents of the ’65 model.

In addition to Wimbledon White, 1966 GT350s were available in Raven Black, Sapphire Blue, Candy Apple Red, and Ivy Green. (Photo courtesy of diyford.com.)

What’s more, you could now get your GT350 in a spate of new colors other than Wimbledon White, including Raven Black, Sapphire Blue, Candy Apple Red, and Ivy Green. Additionally, the famous Shelby GT350H models were built especially for Hertz Rental Cars in 1966, featuring a unique Raven Black and gold color scheme. Wanna-be racers could now trash someone else’s Shelby for a weekend at their favorite track.

The smaller exterior differences included a revised finish on the grille, new exterior mirrors, a unique GT350 gas cap, a slightly altered design to the rocker stripes, and backup lights under the rear bumper.

On the inside, the changes for ‘66 were a new instrument cluster and dash-mounted “tach in a can,” a change in seat upholstery, fresh door panels, Shelby door sill labels, and a revised rear deck. Fold-down rear seats were, at last, an option.

The “tach in a can.” (Photo courtesy of the Collector.)

More rare than the “R” models, and rarer still than the Hertzs, was the aborted introduction of a convertible GT350 for the 1966 model year.

Legend has it that that the origin of this project actually stemmed from a comment by a celebrity client of Shelby’s.

Bob Shane, of the chart-topping pop group, The Kingston Trio, had already been a convert to the cult of Shelby, having previously bought a 1963 260 Cobra and a ’65 289 Cobra.

Through these two purchases, Shane and Carroll Shelby had become personal friends. Shane offhandedly mentioned to Shelby one day that if a convertible version of the GT350 were ever to be produced, that he would be the first in line to snap one up. Shelby allegedly agreed with his buddy that the idea appealed to him.

Bob Shane’s unexpected 1966 GT350 convertible. (Photo courtesy of hoctcars.org.)

Flash forward several months, and an astonished Bob Shane received a phone call from Shelby American that his brand new, Candy Apple Red 1966 GT350 convertible was ready for him to take possession of. He picked the car up on July 7, 1966, at San Francisco Shelby dealer, S&C Motors.

As to whether or not Shane’s interest was truly the initial spark that prompted Carroll Shelby to build a convertible is not known, but regardless, it is a documented fact that in April of 1966, Shelby American purchased four, first-gen Mustang convertibles from Ford to use as prototypes for a drop-top GT350. Two of the cars were four-speeds and two automatics, and all were equipped with air conditioning.

The Ivy Green convertible. (Photo courtesy of the coolector.)

The four cars were equipped with white tops and black interiors, and bore the last serial numbers of 1966 Shelby production. One was painted in Sapphire Blue, another in Springtime Yellow (a color from the standard Mustang catalog), the third in Ivy Green, and the fourth, the one that became Bob Shane’s car, in Candy Apple Red.

All four convertibles were given the standard GT350 conversion treatment, although the side scoops were not functional on the cars because of interference from the folding top mechanism. All of the convertibles rolled on the optional, chrome Magnum 500 wheels.

The side scoops on the convertibles were non-functional. (Photo courtesy of diyford.com.)

In addition to Shane’s car, the Sapphire Blue car was also immediately given to a new owner, manager of Ford’s Special Vehicles group, Ray Geddes. That left the yellow and green cars for Shelby to evaluate the convertible’s potential.

Carroll Shelby stated numerous times in interviews that the ’66 GT350 convertibles were amongst his favorite cars that his company produced. He greatly enjoyed driving the test vehicle around for several months, until it was sold off as a used car after reaching a certain mileage as per company policy.

The interior of the Ivy Green car. Note the floor-mounter automatic shifter and the under-dash air conditioning unit. (Photo courtesy of Mecum Auctions.)

In the end, the first generation GT350 convertible would never be sold en masse to the public, as the second-gen body style would be released by Ford as a 1967 model. The road-testing conducted with the 1966 GT350 drop-tops did, however, prove the viability of a convertible in the Shelby line, and as a result, both GT350 and GT500 second-gen convertibles would be sold beginning in 1968.

While those models are highly coveted today, they are nowhere near as desirable as the four 1966 GT350 convertibles produced. Proof of this fact is that in July of 2020, the Ivy Green car sold at the Mecum Auction in Indianapolis for $1.1 million.

A fair price to pay for such an amazing Rare Ride.

About the author

Rob Finkelman

Rob combined his two great passions of writing and cars; and began authoring columns for several Formula 1 racing websites and Street Muscle Magazine. He is an avid automotive enthusiast with a burgeoning collection of classic and muscle cars.
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