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.
OK, thanks for the answer.
The original ECU is Motronic ML 4.1. It has 2-row 35-pin connector, which I'm planning to use for all connections. The orignal wiring may be used as well.
List of the sensors and actuators:
- TPS is a switch-type and needs to be replaced ( 0 280 120 315 )
- Does anyone know a TPS which would be a direct fit?
- Some sources claim that a TPS from 155 would be of a potentiometer type? I thought it should be the same if it's taken from a 8-valve engine.
- IAT is integrated to air flow sensor
- replace with a sensor from a turbo charged car
- RPM sensor is VR-type Bosch sensor. This should work just fine. ( 0 261 210 036 )
- Use the original coolant temperature sensor
- Ignition coils from a 155TS. It's a DIS-type system. Bosch spare part number is 0 221 503 407. http://www.bosch-motorsport.de/de/aktuatoren/pdf/ignition_coils/2x2.pdf
- Can these be used without IGBT? Or do I always need a driver transistor for these outputs even if the module includes an ignition amplifier.
- Bigger injectors needed. Probably something around 350cc/min.
- Should the injectors be low- or high-Z?
- IAC. Use the original. 2-pin Bosch device. Apparently the same than in older Opel Vectras ( 0 280 140 516 )
- Is it OK to drive this with one of these interfaces: "4*MC33151D FETdrivers onboard "
The shopping list:
- GenBoard v3.3 ( the partially assembled version )
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