1968 AC 428

There have been several perfect unions in the automotive industry that, by all logic, should have been successful - but weren't. The ASA 1000 was essentially a smaller version of the Ferrari, with similar styling and mechanical fortitude, but fewer than 100 units were built, far below the anticipated volume of over 3000 cars annually. The Apollo 5000GT (Vetta Ventura) proved that 'success in the automotive world is not always measured by financial statements alone.' They wore attractive Italian aluminum coachwork by Intermeccanica and were powered by Buick V8 power, but only 88 examples were eventually built between 1962 and 1965. Annual production of the Facel Vega vehicles rarely exceeded 100 units annually. The Swiss-based Monteverdi and Italian-based Iso Autoveicoli S.p.A. followed similar 'hybrid' formulas with production remaining exclusive.

Among the unions that were successful, both in popularity and in profitability, was the AC/Shelby Cobra. This was the driving inspiration for AC Cars which wanted to reconfigure its potent sports car into a luxurious Grand Routier. The formula would incorporate similar key components, including Italian styling, American V8 horsepower, and the Cobra MK III coil-suspended chassis with a 6-inch increase in the wheelbase. The chassis was dispatched to Italy to be clothed in steel coachwork by Pietro Frua.

Pietro Frua was a leading Italian coachbuilder during the 1950s and 1960s, whose early work included the Fiat 1100C Spyder and the Maserati A6G. Their styling on the Maserati Mistral (1963 - 1970) would share numerous similarities with the AC 428, including the gently sloping hood flanked by round headlights, the fastback rear styling, and the wraparound windshield. While similar, only the front quarter windows and door handles were shared. Both had a similar footprint, with the Mistral's wheelbase of 94.5 inches and an overall length of 177.2 inches being very similar to the 95-inch wheelbase of the AC and an overall length of 176 inches. The Mistral, however, was powered by a 3.5-liter inline-6 (eventually growing to 4 liters), while the AC Frua (also known as the AC 428) was given a Ford 428 cubic-inch (7.0-liter) V8.

The chassis of the AC Frua used square and rectangular tubing connecting the frame to the steel body. Body styles included both a coupe (fastback) and convertible, with their boot lids and bonnets formed from aluminum. The suspension was adjustable independently with coil springs, double triangular wishbones, and hydraulic telescopic shock absorbers. Stopping power was courtesy of 'Girling' 3-piston disc brakes and steering was by Rack and Pinion.

The 'big block' Ford FE 428 engine had a bore of 104.9mm and a stroke of 101.2mm. It had a compression ratio of 10.5:1, hydraulic lifters, Autolite or Holley four-barrel carburetors, and delivered 345 horsepower at 4,600 RPM and 474 lb-ft of torque at 2,800 RPM. Some examples received high-performance, cross-bolted main Ford 427 side-oiler engines with 385 horsepower and 460 ft-lb of torque. Transmission options included a fully synchronized four-speed close-ratio Ford Toploader or a three-speed Ford C6 automatic. Since these vehicles leaned more towards 'touring' than 'sport,' the majority were outfitted with the automatic transmission. Power was sent via a Salisbury limited-slip differential with a 2.88 axle ratio for the automatic transmission and 3.08 for the manual.

Like so many great Grand Touring vehicles throughout history, the AC Frua was a victim of 'outside' influences. The energy crisis of the early 1970s was instrumental in its demise, along with Ford's ability to supply engines, and Frua's production limitations. Shipping the rolling chassis to Turin and back again after the bodies had been installed was both time-consuming and expensive, resulting in delayed deliveries. Due to the inflated price, the 428 was more expensive than the contemporary Aston Martin DB6.

Just 29 convertibles would leave the Thames Ditton factory along with 49 coupes, 31 of those with right-hand drive. Near the close of production, several prototypes were produced including a four-door version of the coupe and a streamlined and modernized version of the convertible, complete with electrically operated 'pop-up' headlights.

The AC Frua weighed a mere 1,416kg and was capable of sub-six-second 0-60mph times and 0-100 mph times of approximately 14.5 seconds. The top speed was achieved in excess of 140 mph.

The AC 428 outshone its rivals in terms of speed and comfort but was limited due to its price and lack of the prestigious mystique as similar thoroughbreds, including Maserati, Ferrari, Aston Martin, and Lamborghini.

by Daniel Vaughan | Nov 2021