The Alfetta name ("little Alfa" in Italian) came from the nickname of the Alfa Romeo Tipo 159 Alfetta, a successful Formula One car which in its latest 1951 iteration paired a transaxle layout to De Dion tube rear suspension, like the modern saloon.
The Alfetta introduced a new drivetrain layout to the marque. Clutch and transmission were housed at the rear of the car, together with the differential for a more balanced weight distribution, as used on the Alfetta 158/159 Grand Prix cars. The suspension relied on double wishbones and torsion bars at the front and a De Dion tube at the rear. When leaving the factory all Alfettas originally fitted Pirelli Cinturato 165HR14 tyres (CA67).
The rear de Dion transaxle found on the Alfetta and derivatives- GTV, 90 and 75- provided these cars with excellent weight distribution. The advantages to handling were noticed in contemporary commentaries by motor testers such as Vicar. The transaxle design, in combination with a Watt's parallelogram linkage, inboard rear brakes and a well-located de Dion rear suspension, resulted in excellent traction and handling. The front suspension design was also unusual in that it incorporated independent longitudinal torsion bar springs acting directly onto the lower wishbones and with separate dampers.
The Alfetta saloon was launched in 1972, equipped with a 1.8-litre four-cylinder. It was a three-box, four-door notchback saloon ("Berlina" in Italian) with seating for five designed in-house by Centro Stile Alfa Romeo; the front end was characterised by twin equally sized headlamps connected to a central narrow Alfa Romeo shield by three chrome bars, while the tail lights were formed by three square elements. At the 1975 Brussels Motor Show Alfa Romeo introduced the 1,594 cc (97 cu in), 108 PS (DIN) Alfetta 1.6 base model, easily recognizable by its single, larger round front headlights. Meanwhile, the 1.8-litre Alfetta was rebadged Alfetta 1.8 and a few months later mildly restyled, further set apart from the 1.6 by a new grille with a wider central shield and horizontal chrome bars. Engines in both models were Alfa Romeo Twin Cams, with two overhead camshafts, 8-valves and two double-barrel carburettors. Two years later the 1.6 was upgraded to the exterior and interior features of the 1.8.
In 1977 a 2.0-litre model was added. Launched at the March Geneva Motor Show, the Alfetta 2000 replaced the outgoing Alfa Romeo 2000. This range-topping Alfetta was 10.5 cm (4.1 in) longer than the others, owing to a redesigned front end with square headlights and to larger bumpers with polyurethane inserts; the rectangular tail light clusters and C-pillar vents were also different. Inside there were a new dashboard, steering wheel and upholstery materials. Just a year later, in July 1978, the two-litre model was updated becoming the Alfetta 2000 L. Engine output rose from 122 PS to 130 PS (DIN); inside upholstery was changed again and dashboard trim went from brushed aluminium to simulated wood. The Alfetta 2000 was sold as the Alfa Romeo Sport Sedan in the United States, where "Alfetta" did not have the same cachet as in Europe. The 2000 received fuel injection in 1979.
A turbodiesel version was introduced in late 1979, the Alfetta Turbo D, whose engine was supplied by VM Motori. Apart from a boot lid badge, the Turbo D was equipped and finished like the top-of-the-line 2000 L both outside and inside. Therefore, it received a tachometer—very unusual in diesels of this era, but no standard power steering, in spite of the additional 100 kg (220 lb) burden over the front axle. The turbodiesel, a first on an Alfa Romeo's passenger car, was of 2.0 litres and produced 82 PS. The Alfetta Turbo D was sold mostly in Italy and in France, as well as a few other continental European markets where the tax structure suited this model.
In 1981 Alfa Romeo developed in collaboration with the University of Genoa a semi-experimental Alfetta version, fitted with a modular variable displacement engine and an electronic engine control unit. Called Alfetta CEM (Controllo Elettronico del Motore, or Electronic Engine Management), it was shown at the Frankfurt Motor Show. The 130 PS (96 kW; 128 bhp) 2.0-litre modular engine featured fuel injection and ignition systems governed by an engine control unit, which could shut off two of four cylinders as needed in order to reduce fuel consumption. An initial batch of ten examples were assigned to taxi drivers in Milan, to verify operation and performance in real-world situations. According to Alfa Romeo during these tests cylinder deactivation was found to reduce fuel consumption by 12% in comparison to a CEM fuel-injected engine without variable displacement, and almost by 25% in comparison to the regular production carburetted 2.0-litre. After the first trial, in 1983 a small series of 1000 examples was put on sale, offered to selected clients; 991 examples were produced. Despite this second experimental phase, the project had no further developments.