Originally Posted by alfavirusnz
I remember reading in the `70s or thereabouts (when the cars were current )that Alfa was experimenting with VVT in the `70`s when the Alfetta Berlinas came out and that there were Alfetta Taxi`s in Milan that were used as a quiet proving ground for some of this technology.
Well, that was another experiment, and I don't remember it included VVT. The Milan taxis you refer to were fitted with a "modular" engine controlled by Alfa's own electronic management system called "CEM" (controllo elettronico motore). Actually, at idle and low revs, low charge, only two cylinders were active. To avoid heat distorsion, at each switch of the system, a different couple of cylinders was turned off. This worked pretty well, a bit rough on the transistion between 2 and 4 cyl. cycles, but at an acceptable level. Even a GTV6 with an atmo bank and a a turbocharged one was developped in 1984 on the same principle of modularity, the 3 atmo cyl. running all the time, and the turbo one switching on when power was needed.
Tubolarespider: a 6C2500 with "Ala spessa" body ran the 1940 Mille Miglia with the fuel injection system. It's described in Angelo Tito Anselmi's book "6C2500". Remember that the Daimler Benz 601 engine on the Messerschmitt fighters (and the license-built Alfa Romeo RA1000 RC41) featured direct injection during WWII.
Ferrari had also developped a variable timing-variable lift system in the 70s, for racing use, where the cams had a conic shape, so that the whole camshaft was moved fore and aft, and the cam followers thus were driven by a different profile. Too fragile and too complicated. BMW doesn't move the camshaft, AFAIK
, with its valvetronic system. It acts on the cam follower instead. Fiat is developping the "famous" Uniair system that will dispense with the air manifold butterfly (as does the BMW system), but it has another principle: it's an hydraulic system between the cam follower and the valve. Let's see when it will be introduced. Basically all those systems, including the Alfa CEM tried to address the losses by "pumping" vacuum at low charge
Spica was lso an Alfa subsidiary, and I would be interested in the documentation you quote