I'm planning on installing VEMS on my '89 Alfa Romeo 75 Twin Spark.
I'd like to use the original wiring so I'll probably end up putting VEMS board inside a spare Motronic box. I've checked that almost everything should be fine, even the intake valve timing solenoid can be controlled easily, but how about ignition? Because of the twin spark system there are two ignition units (coils and dwell-capable ignition modules for them). Both plugs in each cylinder are ignited at the same time.
- How should I connect the ignition units? Since they both have their own ignition modules, could I just control both modules from the same signal?
- I think so. Note that this is NOT parallel connection, since the outputs are independent. Only the control signal goes to both units, that is one output to 2 inputs. This is valid, given that current consumption of the input is not too big (which it should not be, for an ignition module with internal driver).
However, check the polarity that the module needs on the control input.