About two thirds of the way through the 1968 model year, Shelby introduced the GT500KR, which of course stood for King of the Road. The cars were equipped with the new 428 Cobra Jet, which utilized the 428 Police Interceptor block from the GT500, but with new Cobra Jet heads featuring larger valves and combustion chambers, plus a nodular crank, stronger connecting rods, dished pistons, high rise aluminum intake manifold, Holley 735cfm double pump carburetor, larger diameter high-flow exhaust system, and functional Ram Air induction routed directly from unique dual functional scoops on a revised fiberglass hood and front fascia.
The KR also received special engine compartment chassis bracing, uprated rear brakes and heavy duty wheel cylinders in addition to adjustable Koni shocks (with staggered rear layout arrangement on 4-speed equipped cars) for the suspension, which was already upgraded for 1968 with variable rate springs, and larger front sway bar.
And the KR was, indeed, an extremely competent package, out-handling all but purest sports cars, delivering want everyone knew to be well in excess of 400hp (even though it was comically rated at 335hp/440lb-ft for insurance purposes), and with an aggressive presence and brash red Cobra Jet badges that led the road test editors at Car Life magazine to observe, "The car is so impressive, so intimidating to challengers, that there are no challengers. The KR breeds confidence bordering on arrogance."
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