Born on the back of the Cobra two-seat roadsters, AC decided to move up-market and build a larger and altogether more civilised car. They had a fantastic and proven race-bred chassis in the Mk III Shelby Cobra, and their close relationship with both Shelby and Ford ensured an adequate supply of engine and running gear.
Derek Hurlock, who now oversaw the family AC concern, eyed the success of the emerging market for fast sports GT cars and thought AC had the platform to build such a car using the simple-to-maintain Ford power plants. The Mk III Cobra chassis was lengthened by six inches and sent to Italian coachbuilder Frua, who designed an attractive fastback coupe and trim for the new car. “The 428 fits my image of a true GT car — like anything exclusive, especially hand-built from craftsmen, it costs a lot of money,” Hurlock said. The AC 428 is the only production GT car that offered fully adjustable independent front and rear suspension, a valuable legacy of the Shelby racing heritage. Make no mistake, this is a seriously fast car that lopes from 0–60 mph in six seconds, has a top speed of over 140 mph and is capable of cruising all day at 130 mph if required. An exclusive club indeed!
Thinking back to the early 70’s when this car was built, the competition were offering similar style ‘fastbacks’ such as the Ferrari Daytona, Lamborghini Miura, Iso Griffo and Maserati Ghibli. All of which today are incredibly rare, desirable and expensive collector cars. The AC Frua Fastback is by far the rarest of all of the above as there were only 52 cars ever built in fastback form, of which only around 44 cars are believed to still exist today. Compare that to the 1,284 Ferrari Daytona’s built and this AC Frua Fastback represents an incredible piece of history and for a fraction of the price of a Ferrari Daytona. Ok, so the 428 doesn’t run a V12 engine but a Cobra 427 big block V8 is still able to offer just as much of a trill factor, especially this engine and this set up as offered today in Chassis CF69.
In the cars current ownership it has been converted into the competitive 'fast-road' specification running custom aluminium splitter, side skirts and rear spoiler that give the car better performance on hill sprints which this car has been predominantly used for when competing at places such as Goodwood. Generally in excellent condition with only a few cracks in the paintwork here and there this car is by no means a factory fresh restoration however presents very well indeed.
Fitted with a full roll cage and FIA approved Cobra bucket seats and fire extinguishers this car is ready to be competed at hill-climb or sprint events. The tyres currently fitted to the car are Michelin Pilot Sports. The owner has competed this car for the past 30 years at AC owners club events and hill climbs across the UK.
This particular car, chassis CF69 is currently fitted with a rare 1968 Ford Nascar side-oiler engine which were never built in large numbers. The side-oiler was selected as it could handle substantial modifications (hence the Nascar usage). Specificially this engine has a forged-steel cross-drilled crank stroked to displace 8.3 litres/482 cubic inches. Cross-bolted main bearing caps and screw in core plugs, solid tappets and aluminium Drove roller rockers, a high-lift camshaft, all fitted with ARP grade eight bolts, producing approximately 580lb.ft of torque. Seven quart Canton oil pan with trapdoors and windage tray, Valvoline semi-synthetic racing oil with aluminium oil catch tank. Remote oil filler with Goodrich stainless steel hoses with twin oil coolers.
The engine was built by the guru of American Ford V8’s, Stuart Mathieson of Mathwall engineering established in the 1960’s. Stuart started as an apprentice at Aston Martin producing Roy Salvadori and Carroll Shelby’s DBR1 Le Mans winning car. He then moved to Alan Mann racing and in 1959 he worked on the Daytona Cobras building their engines, eventually clinching the World Sports Car Championship at Reims. Stuart then built the engines for the GT40 project driven by Jackie Steward and Graham Hill. All of his engines are dyno tested on his famous dynometer of Dan Gurney’s All American Racing heritage.
The gearbox runs a Ford C6 transmission which has been upgraded to full manual twin clutches, rebuilt B&M Holeshot torque converter with 2800 stall speed, cast aluminium extra two quart oil pan with TCI Max Shift transmission fluid remote oil cooler with braided hoses. Manual action B&M Pro stick shifter meeting NHRA and IHRA requirements with reverse lockout. The gearbox was upgraded and rebuilt by Alders of Hailsham Sussex in 2015.
Holley street Avenger 770 cfm carburettor with four barrel and vacuum secondaries enclosed in a custom aluminium cold box. Holley 110 gph fuel pump housed in the boot running at 7lbs psi with two filters. Aluminium performer rpm cylinder heads, aluminium period Cobra Le Mans rocker covers (included with the car) aluminium Street Master single-plane inlet manifold and aluminium high performance water pump, large custom aluminium radiator with two stage Kenlowe fan and Evans waterless coolant which boils at 180 degrees centigrade. Custom made stainless steel headers with three inch exhausts. Edelbrock silencers which exit from the sides plus 2 removable reducers (included in the sale). Mallory electronic Unilite distributer and Pro master coil. Blue Max eight millimetre spiral-core high-temperature high-voltage HD leads. Twin circuit servos with twin master cylinders separating the front and rear brakes with Automec silicone brake fluid which has a high boiling point of 260 degrees centigrade. APS silicone hoses and a lightweight Powermaster XS high torque starter motor is installed making this a reliable mechanical set up to this monstrous big-block V8 fastback.
Vehicle Specification / Options
Chassis CF69 is even more unique in having been optioned with aluminium doors, boot and bonnet skin which were fitted by AC at their Brooklands factory in the 70s. This is a truly unique opportunity to acquire one of the very few remaining AC 428 Frua Fastbacks to either compete as it is or to revert back to period factory specification. A large number of parts are included in the sale to help with the conversion back to period specification. From our understanding the only parts not included are the original engine (was blown, but an original type engine that was fully re-built and is ready to go in can be included at the right price), one of the rear quarter window glass was smashed and so needs replacing and the cars original interior (seats, carpets etc).
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