ALPINA A-Motronic for BMW ALPINA B7 S Turbo E12 and E24
In 1978, ALPINA produced a groundbreaking automobile - the B7 Turbo of the E12 and E24 model generations. With the even more powerful B7 S Turbo models launched in 1981, Bovensiepen underlined its expertise in high-performance automobiles. Packed with revolutionary technology for the era, such as a computer-controlled ignition and the PIERBURG DL injection system, the E12 became the fastest production saloon in the world. The PIERBURG DL system, a mechanical injection system, works according to the principle of air mass measurement and continuously injects a carefully measured amount of fuel into the intake manifold. The injection is controlled via a spatial cam; the controlled variables are the air quantity and the intake manifold vacuum.
Unfortunately, 46 years after its first introduction, this injection system has become susceptible to causing problems or even failure. Due to changing gasoline qualities, a long period of inactivity and, above all the unavailabilty of spare parts, maintaining the original PIERBURG DL system is becoming increasingly difficult and time-consuming. ALPINA has developed and engineered a complex replacement solution for owners of these rare and now very valuable vehicles - the ALPINA A-Motronic.
The function and usability of the vehicle, even after long periods of inactivity, is ensured by the electronically controlled ALPINA injection and ignition. Furthermore, the new injection system does not significantly change the original appearance of the engine compartment – quite a feat and a prerequisite for receiving the H license plate in Germany.
A replica of the PIERBURG DL injection system acts as a fuel pressure accumulator in the ALPINA A-Motronic system. The electrically controlled injection valves are supplied via original fuel lines. The mechanical fuel pump and the cold start valve are no longer required. The fuel enrichment required for cold-start is carried out by the new engine electronics. The additional air valve is replaced by an idle control valve. The additional temperature sensor for recording the coolant temperature for the engine control is located in the thermostat housing. The mechanically vulnerable ignition distributor is no longer required. Instead, the space gained is used to accommodate the phase encoder - housed in the stylish, CNC-milled ALPINA cover. The signal generator for the phase generator replaces the distributor finger. The use of a Hall sensor enables fully sequential injection and semi-sequential ignition. A fully active 3x2 ignition coil ensures that the mixture ignites safely even under the toughest operating conditions, which, like all other installed actuators and sensors, also meets the strictest automotive standards.