AC Frua

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AC Frua

Manufacturer	AC Cars
Production	1965–1973 81 made
Class	Coupé Convertible
Engine(s)	7 litre V-8
Transmission(s)	4-speed manual 3 speed automatic
Wheelbase	95 in (2413 mm)
Length	176 in (4470 mm)
Width	68 in (1727 mm)
Height	49 in (1245 mm)
Curb weight	3150 lb (1430 kg)

The AC Frua or AC 428 is a British GT car of the 1960s and early 1970s. Built by AC Cars from 1965 to 1973, it is extremely rare with only 81 cars built in total, 49 coupés (known as fastbacks), 29 convertibles and 3 special bodied. The car is built on the AC Cobra 427 Mark III race-bred coil springs chassis but extended by 6 inches (150 mm). Chassis were built at the AC plant in England then shipped to Frua's workshop in Italy where the body was fitted and then sent back to England to have the power train and trim added. The cost was huge and the cars could not be sold at a competitive price. Unlike similar cars such as the Iso Grifo, Iso Rivolta, and Monteverdis and De Tomasos of the period, the AC Frua features fully independent racing based coil spring suspension. It is often confused with the very similar looking Maserati Mistral also designed by Frua. (There is a common belief that the two cars share most of their body panels, but in reality only the front quarter windows and the door handles are the same.)

1 Construction
2 Performance
3 See also
4 External links

[edit] Construction

1971 AC Frua convertible

Construction was similar to most Italian supercars of that era with square and rectangular tubing connecting the steel body to the frame. There were aluminium bonnets & boot lids. The design was intricate and prone to rust. Because of its huge 4 inch (100 mm) tubular chassis, the car was immensely rigid in both coupé and convertible versions. Chassis numbering went as follows: CF## for cars sold in Britain and CFX## for export models.

1968 AC Frua coupe

The AC Frua was never fully developed because AC Cars lacked the financial means. The car's main drawback, which is also common to the similarly-engined big-block United States muscle cars of the period, is a tendency to dissipate the heat produced by the huge engine into the cabin. But this design flaw can be overcome by using modern insulation on the firewall and under the floor.

[edit] Performance

The AC Frua competed with Ferrari, Lamborghini, and Maserati models. Built over a stretched AC Cobra 427 chassis, the car had immense performance; the big-block Ford FE engine had larger capacity, more torque and more power than similar Italian cars, but in a car of similar weight.

John Mclellan said in his book "Classic ACs, Auto Carrier to Cobra" that Dereck Hurlock once said to journalist Mike Tailor: " I like the 428 because it fits my image of a true GT Car". He also quoted the magazine Autocar which said the following about the AC 428: "Like anything exclusive, especially from craftmen, it costs a lot of money. For this you get one of the fastest cars on the road, guaranteed to make an impression anywhere, and backed by a small company who cares. This one AC that joined that select company of very fast, very luxurious touring automobiles which moved effortlessly from current model to collector's piece".

Due to the rarity of the car, body parts can be very difficult or impossible to obtain. However, all mechanical parts are available through Ford or various Cobra suppliers. The car is extremely reliable and maintenance is easy and relatively inexpensive compared to other exotics of the period because of the Ford powertrain and AC Cobra suspension and chassis.

With a little tweaking the car can be made as quick as, or even quicker, than a Cobra because of its improved aerodynamics, and the chassis is more than able to handle vast amounts of power. Five hundred horsepower (370 kW) is relatively easy to achieve with the 428 motor and the 427 "side oiler" motor can easily achieve in excess of 600 hp (450 kW) on "pump gas" (91 octane). With this type of power the car is one of the fastest road going automobile of that era.

Towards the end of the production run a couple of prototypes for an extended range were produced. There was a four door version of the coupe and a more streamlined version of the convertible that included electrically operated "pop-up" headlamps. Neither were developed due to the precarious state of the company finances.

A few of the coupes have been destroyed in the past and converted into Cobra replicas— but as pricing has been rising steadily in recent years, this practice has stopped. It is now much cheaper to buy a Kirkham rolling chassis to build an exact Cobra replica than to butcher an AC Frua.

AC Frua Technical Data
Chassis	"AC Cobra 427 Mark III" four inch (100 mm) tube frame extended by 6 inches (150 mm). Front engine, rear drive.
Engine	Iron "big block" Ford FE 428, some models fitted with higher performance crossover bolted Ford 427 engine (side oiler). Hydraulic lifter, Autolite or Holley four barrels carburator. (Specifications can vary substantially between each car).
Bore & stroke	104.9 X 101.2 mm, 10, 5:1 compression.
Capacity	428: 7,014 cc, 427: 6,965 cc.
Power	428: 345 hp @ 4,600 rpm, 427: 385 hp @ 5600 rpm
Torque	428: 642 Nm @ 2,800 rpm, (462 ft·lbf) 427: 624 Nm @ 3200 rpm, (460 ft·lbf)
Transmission	Fully-synchronized 4 speed Ford "Toploader Transmission" close-ratio or 3 speed automatic Ford C6 transmission.
Steering	Rack & Pinion.
Front suspension	Fully adjustable independent suspension with double triangular wishbones, coil spring hydraulic telescopic shock absorbers.
Rear suspension	Adjustable independent suspension with double triangular wishbones, coil spring hydraulic telescopic shock absorbers.
Differential	Salisbury, limited slip. Ratio: Automatic 2.88, Manual 3.08.
Brakes	Four discs power assisted "Girling" 3 pistons, dual remote servo assistance.
Body	Coach-built steel body over extruded rectangular and square tubing.
Measurements	4,470 X 1,727 X 1,245 mm; Wheelbase 2,413 mm.
Unloaded weight	1,430 kg
Maximum speed	Manual Transmission: More than 245 km/h, 0 to 100 km/h: 5.4s (Autosport Magazine); Automatic Transmission: 220 km/h, 0 to 100 km/h 5.7s.
Fuel consumption	17.2 liters/100 km
Production life	1965 to 1973
Number of cars built	49 coupes, 29 convertibles and 3 special bodied cars.