Classic Car Catalogue

Hartnett 1951



AFTER three years of preparation, the production version of the Hartnett car has just been shown in Australia. Mr. L. J. Hartnett, managing director of the Hartnett Motor Co., Ltd., of Melbourne, states that small numbers are already being made and full production is hoped for later in the year. Main features of the design, such as the cast aluminium alloy structure, the air-cooled flat-twin engine driving the front wheels and the variable-rate coil spring rear suspension, are derived from the prototype designed by J. A. Grégoire and built for Aluminium Francaise (AFG) in 1943, but the all-metal four-seater tourer coachwork has been designed in Australia. Later it is hoped to produce a saloon on similar lines. Current prices of the Pacific tourer-based on present material costs is £549 (Australian), but the aim is to retain the : position of lowest priced family car on the Australian market, even if price changes are made necessary by increased material costs. The air-cooled, flat-twin engine retains the original dimensions of the Grégoire prototype and is largely made of light alloys. Cylinder barrels have easily replaceable sleeves of chrome molybdenum with a honed finish. Connecting rods are light alloy forgings and main bearings are steel shells with white metal liners. Crankcase ventilation is controlled by a rotating valve which is driven from the camshaft, and opens to relieve pressure when the two pistons approach the bottoms of the bores. A single downdraught Solex carburettor is used, with exhaust heated hot spot. As the gear box forms part of the front drive unit all gears are indirect and top is geared up, giving an overdrive effect. The electrical system is 6-volt, with constant voltage control. A 5-gallon fuel tank is carried under the bonnet, feeding the engine by gravity. The body has seats for four, with space for luggage, spare wheel and tools in the tail reached from behind the rear seat: Steering is by rack and pinion. A maximum speed of 70 m.p.h. is claimed and the fuel consumption is put at 60 m.p.g. with a car weighing 1,000 lb, although only 53 m.p.g. was claimed for the original Grégoire prototype which weighed 948 lb.

Engine.-Flat twin, o.h.v., air cooled, 72 x 73 mm, 594 c.c.. aluminium barrels with hardened liners, light alloy connecting rods. Compression ratio 6 to 1, 19 b.h.p. at 4,000 r.p.m.
Transmission.-Dry single-plate clutch, four-speed gear box and differential in unit driving front wheels. Gear ratios, 4.46, 5.71, 8.79 and 17.58 to 1.
Suspension.-I.f.s. by transverse leaf springs. Independent rear suspension by trailing arms and coil springs in tension.
Brakes.-Girling hydro-mechanical with hand brake on rear wheels.
Wheels and Tyres.-Steel rims on aluminnium alloy spiders with cast iron brake drums. 4.50-15in tyres.
Dimensions.-Wheelbase 6ft 6 3/4in; length 11ft 6in; track 4ft; width and height 4ft 7 1/2in; ground clearance 7 1/2in; weight unladen, tourer 1,000 lb; saloon 1,050 lb.