This is a 1968 Shelby Mustang GT500KR “King of the Road” convertible, it’s one of just 517 convertible examples that were made, and it was the most powerful Mustang ever at the time of its release.
The Shelby Mustang series had debuted in 1965 with the GT350 model. This vehicle would quickly establish racing credentials for the entire Mustang family, winning the SCCA B-Production championship for three straight years from 1965 to 1967.
Fast Facts – The Shelby Mustang GT500KR
- The Shelby GT500KR was introduced in 1968 as a more powerful version of the standard Shelby GT500. The “KR” stands for “King of the Road,” signifying its performance advantage over both the GT500 and other American muscle cars of the era.
- At the heart of the GT500KR was a 428 cubic-inch Cobra Jet V8 that officially produced 335 bhp, though it’s widely believed that the actual output was well over 400 bhp. This enabled the GT500KR to do the 0-60 mph run in 6.5 seconds, a remarkable feat for the time.
- The GT500KR was fitted with a number of lightweight fiberglass parts including the nose section, hood, rear tail light panel, deck lid, quarter panel extension, and side scoops. The hood scoop was functional on the GT500KR, and the car was given “Cobra Lemans” valve covers as a reference to the success of the Ford GT40 at Le Mans.
- The Shelby GT500KR was produced for only one year, 1968, with a total of 1,570 units made including 1053 fastback coupes and 517 convertibles. This limited production has made the model highly sought after by collectors today, with pristine examples fetching ever higher prices at auctions and in private sales.
The World’s Most Powerful Mustang
At the 1967 New York Auto Show, Ford would debuted what was to be their most powerful Mustang ever up until that point in history – the Shelby GT500KR. It was so powerful in fact that they lied about its output, significantly under-rating it so as not to attract too much attention from the Department of Transport or the insurance companies.
The Shelby Mustang GT500KR “King of the Road” was based on the Shelby GT500, but was powered by a more powerful version of the 428 cubic inch V8 known as the Cobra Jet. This engine was said to be good for 435 bhp and 440 lb ft of torque, offering blistering straight line performance that could match almost anything on earth. Image courtesy of Shelby American.
The official specification sheet for the Shelby GT500KR noted that the 428 cubic inch Cobra Jet V8 was good for 335 bhp and 440 lb ft of torque. It appears that the documentation under-reported the horsepower figure by exactly 100 bhp, as the output was later found to be 435 bhp – making the GT500KR one of the most powerful production cars on earth at the time.
The Shelby Mustang GT500KR
The Shelby Mustang GT500KR was directly based on the earlier Shelby GT500, the big block V8 sibling to the Shelby GT350. Power was provided by the 428 cubic inch (7.0 liter) Ford FE Cobra Jet V8 fitted with high-flow heads, and a dual-quad 600 cfm Holley carburetor.
The engine was fitted with die-cast aluminum valve covers with the script “Cobra Lemans” across the top, a reference to the big block Ford V8s that had powered the GT40 to its back-to-back wins at the 24 Hours of Le Mans in 1966 and 1967.
The GT500KR was fitted with a slew of upgrades over the standard Mustang to better handle this power output, including heavy duty suspension, power front discs, a front-strut brace, wider rear brake drums, a roll bar, power steering, an 8000 rpm tach, and a 140 mph speedometer.
In order to reduce weight and change the look compared to the standard 1968 Mustang, the Shelby GT500KR was fitted with a fiberglass nose section, hood, rear tail light panel, deck lid, quarter panel extension, and side scoops.
The interior of the car looks much like the standard Mustang, with only a few carefully placed decals to show the occupants what they’re actually riding in.
In reality, the Shelby GT500KR was designed to do one thing and do it well – go very fast in a straight line.
The weight of the big block V8 over the front end meant the car was more challenging to get around corners than the lighter Shelby GT350, but the sheer power turned out by this engine made it almost unbeatable in the 1/4 mile, and of course, in the kind of unofficial traffic light races that take place across America every night of the week.
The GT500KR would be made for just a single year, 1968, with a total of 1,570 units made including 1053 fastback coupes and 517 convertibles. Surviving examples are now understandably sought after by collectors, with prices typically stretching well into the six figures for good examples.
The 1968 Shelby GT500KR Convertible Shown Here
The car you see here is one of the 517 original Shelby GT500KR convertibles from 1968. This car was first delivered to Willett Ford in Rockford, Illinois as a special order in #WT6066 Yellow with a power-operated White soft top, a push-button AM/FM radio, and a heater.
The car was given a refurbishment in 1995 when it was repainted, given a new black soft top, the correct GT500KR side stripes, and quad exhaust outlets. It rides on the correct aluminum alloy 15″ wheels with Shelby Cobra center caps, shod with Goodyear Polyglas GT tires.
Ford famously under-rated the horsepower output of the 428 Cobra Jet, claiming only 335 bhp when the car was actually said to produce 435 bhp. This was likely to avoid too much scrutiny from Uncle Sam, not to mention the insurance companies that had to underwrite the cars.
As you would expect for a GT500KR, this car has the heavy duty suspension, power front disc brakes, wider rear drums, power steering, a roll bar, functional hood scoops, and the thicker front anti-roll bar. Inside the car you’ll find two front bucket seats, a center console, a rear bench seat, black carpeting, and wood trim.
The car is now being offered for sale out of Scottsdale, Arizona with a Deluxe Marti Report, refurbishment photographs, and a clean Ohio title. If you’d like to read more about it or register to bid you can visit the listing here.
Images courtesy of Bring a Trailer.
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