Bosch ECU Schematic for 1981 BMW 528i

[Charles]

Michael Glidewell wrote: 
>I wonder if it would be possible to turn the L-jet into a multiport
>injection system by firing each injector individually and possibly 
improve>the city fuel consumption (its 12+ mpg).

    I think you mean "sequential" (vs. batch-fire). It is multiport.

    I'm not sure about your '81 2.8, but the late 70's 3.0 (i.e. 530i) 
had horrible gas mileage because the emission control system was a 
thermal reactor, not a catalyst. A thermoreactor requires about a 
10-15% overrich mixture so that the exhaust is rich enough to burn. 
Also the timing must be retarded to get a hot exhaust. These two 
factors guarantee lousy mileage...
-Charles
('81 745i)