In mid-1968, Ford unleashed a new version of the 428 V8 called the Cobra Jet. It featured a 715-cfm Holley four-barrel carburetor, bigger exhaust manifolds, and a high capacity fuel pump. The 428 Cobra Jet also featured hydraulic valve lifter, a revised distributor curve, and a 10.6:1 compression ratio. The Cobra Jet was conservatively rated at 335 horsepower and 440 lb.-ft. of torque. That horsepower figure was considerably lower than the outgoing 428 V8 offered in the GT500, which was rated at 360 horsepower. So why is that? Well, it’s no secret that manufacturers fudged horsepower ratings in order to keep insurance rates at bay. Those in the know would tell you the actual horsepower output of the GT500 KR was closer to 410 horsepower.
If you think the Shelby GT500 KR looks different than the stock Mustang, you are right. The GT500 KR featured a deep molded fiberglass grille area with rectangular Lucas fog lamps, fiberglass hood with dual air scoops, and air extractors on the rear quarter. The GT500 KR also featured Thunderbird-style taillamps, a flip-down gas filler cap with Cobra badging, and Cobra Jet 428 badging on the front fenders.
So how did the Shelby GT500 KR become King of the Road? It all started when Carroll Shelby had a meeting with Lee Iacocca, Ford’s executive vice president. Iacocca mentioned to Shelby that Chevrolet had been preparing to launch a Corvette called the King of the Road. Marketing materials had been prepared and the car would be publicized in a couple weeks. Shelby was not pleased since he wanted the King of the Road moniker himself. He got on the phone with his lawyer to find out if King of the Road had been registered with the United States Patent and Trademark Office. After learning that it had not, Shelby beat Chevy to the punch and registered the name himself. He then dubbed the Cobra Jet-powered GT500 the KR.
Hot Rod magazine got their hands on the GT500 KR for their November 1968 issue. Their fastback with a four-speed manual transmission sprinted the quarter mile in just over 14 seconds running 102.73 miles per hour. A convertible with a Select-O-Matic three-speed transmission was able to run the quarter in 14.58 seconds at 97.71 miles per hour.
Few buyers got their hands on a 1968 Shelby GT500 KR. Due to a late year start, production of the King of the Road was only around 1,200 units. A labor strike at Ford delayed production and EPA emission testing and certification took a lot longer than expected. Low production numbers could also be one of the reasons the GT500 KR commands so much at auction. A GT500 KR fastback traded hands at Mecum’s Indy 2020 auction for $258,500. A GT500 KR convertible commanded a $209,000 price at Barrett-Jackson’s 2013 Scottsdale auction.
The 1968 Shelby GT500 KR was one of the last great Shelbys before Ford took control of production. Its time might have been short, but the GT500 KR left an impression that’s still felt today. If Ford and Shelby’s relationship hadn’t waned after 1968, there’s no telling what these two could have accomplished. However, one thing is evident. The 1968 Shelby GT500 KR’s legacy will live on for many years to come.