AC Cobra Mark III

The AC Cobra Mark III was built in Britain from 1965 to 1967 with 4.7 L (289 cu in) V8 engine also some with 427 cu in (7.0 L) V8 .

History 

By 1965 and Shelby began to drop the 7-litre Ford engine into an even thrther revised chassis. The basic min tube frame remained but the tubes grew bigger; still more important was the introduction of twin wishbone and coil-spring suspension at each corner replacing the transverse leaf springs. With Ford brain power behind Shelby, the installation
successful. but few were sold in Europe. With the termination of the A.C.Shelby contract and the sale of the name Cobra to Ford, A.C. were left a more than adequate chassis for the 4.7-litre engine: the same chassis, lengthened. provides the basis for the Frua bodied 42S convertible, a superb car in the luxury tradition of A.C.

The AC Cobra Mark III was built until 1967 The engine a V.8 high performance unit manufactured by Ford Motor Co. of America. The front suspension comprises twin wishbones by highly specialised thin wall casting techniques developed by Ford America to reduce weight. Identical to 428 Convertible, but wheelbase 6 in shorter. The new car also had wide wings and a larger radiator opening for cooling. 

Traditional British sports body constructed in 16- and 18-gauge aluminium; leather trim, with carpets to choose. Demountable hood and tonneau; large luggage boot; fuel tank 15 Imp. gal.; spare wheel under luggage locker; maximum speed 150 m.p.h. Dimensions: weight 2,282 lb.; length 13 ft., width 5 ft. 8 in, height'4 ft. 1 in, with soft top erected; wheelbase 7 ft. 6 in., track, front 4 ft. 7 in., rear 4 ft. 6 in.

Inside Carpets are fitted to the floor and transmission tunnel and the seats are upholstered in leather; the door locks at the rear of the panel are operated by a simple leather pull-strap and you have to open the sidescreen and pull the strap to undo the door from the outside. There is a number of instruments on display, The wheel spokes obscure the lower edges of the speedometer and rev-counter the horn operation,a bar in the back of the indicator stalk. There is no padding on the painted metal facia top and its flat surface reflects on to the screen. There is a glove locker on the facia but the rest of the luggage has to go in the boot on top of the spare wheel with 3.9 cu.ft. of luggage space.

The soft hood is held on top of the screen by two pins in the centre which slide into a channel, and at the edges by over-centre clips. Press studs hold it down round the base of the hood, and there is a rubber sealing strip inside; tensioning is provided by a hoop hinged to the main arch. The fabric and the side screens fit into a bag.and takes around two minutes to put back up.Visibility is good with the soft top; the screen pillars are thin and there is plenty of clear sheet in the fabric. With the hood up there are few draughts until you move the sliding sidescreen forward, which is necessary in traffic. On the move you can get cold air in by ram effect at foot level; this is controlled by knobs at either end of the facia. For hot air you have to use the two-speed fan since the system is a recirculatory one; there are flaps at foot level and the screen outlets demist the screen quite quickly.

From 1953, the two-seater body has basically similar with a revised nose coming with the Zephyr engine option and ever wider wing flares along with an ever wider track. With 271 bhp in 21cwt of car, the 289 is extremely fast The unit is extremely tractable and it has an excellent gearbox. Although the cornering attitude of the car is largely dictated by the throttle at road speeds, the way the power is put through to the road, particularly on wet surfaces, is quite remarkable. it is not too impractical but a 15 mpg thirst and frequent servicing might put one off using it as a every day car. You are unlikely ever to get better than about 17 mpg which gives a usable range on the 15-gallon tank of about 220 miles.l

Engine: V.8 built by the Ford Motor Co. of America, 7,016 c.c. along with a high-performance engine also available, providing 400 bhp with single 4-barrel 780 CFM Holley carburettor. at 5,750 r.p.m. at extra cost. 

Capacity 4,727 c.c. (289 cu. in.) with bore and stroke (4.00 x 2.87 (101.6 x 72.9 mm.) ,crankshaft carried on 4 main bearings, lead bronze bearing shells to mains and big ends, compression ratio 11:1, 4-choke Holley carburettor, 270 b.h.p. at 5,850 r.p.m. with 6,500 as recommended maximum; lubrication by pressure pump to bearings; aluminium pistons; Salisbury limited slip differential 3.54 ratio, Borg Warner 4-speed all synchromesh gearbox, ratios 2.20, 1.66, 1.31, 1.00; chassis, suspension, steering and brakes, identical to 428 Convertible, but wheelbase 6 in. shorter.

The gearbox has such excellent ratios and the short stubby gear lever. The pedals are well placed for heel-and-toeing and there is room for the left foot beside the clutch. resting on a piece of floor.The heavy clutch with a long travel itself grips smoothly and well but its long travel more final
drives are Salisbury 4HU with limited-slip differential.

PERFORMANCE: 289 cu in

• Fuel consumption: 19 ml imp gal, 15.8 ml us gal
• Max speed: 150 mph, 241.5 kmlh
• Max power (SAE): 270 hp at 5,750 rpm
• Max torque (SAE): 312 1b ft, 43.1 kg m at 3,400 rpm
• Max engine rpm: 7,000
• Specific power: 57 hp/l
• Power weight ratio: 7.9 lb/hp, 3.6 kg/hp
• Acceleration standing 1/4-mile 14 sec, 0—50 mph (O—80 km/h) 4 sec