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?
- Q: 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.
- A: Yes, it really is. The type is 0280122001 (HÜCO: 13 8601 ).
- 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
- There is no chance these could be used without IGBT, because they don't have GND and supply besides the 2 input pins (since only 3 pins! => no GND input => this module does not include an ignition amplifier).
- A: OK. I forgot that the coils are driven by two of this type of modules( 0 227 100 201 ): http://www.transpo.de/cgi-win/product.exe?BM346 What do I need to drive these?
- Bigger injectors needed. Probably something around 350cc/min.
- Q: 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 )
- Q: Is it OK to drive( PWMing ) this with one of these interfaces: "4*MC33151D FETdrivers onboard "? Are these interfaces meant to drive FETs and they cannot be used directly? Since IAC is an inductive load, do I actually need IGBT instead of FET?
Link to HÜCO parts catalog: http://www.hueco.com/assets/PDF/MM_Katalog04.pdf
The shopping list:
- 1 x GenBoard v3.3 ( the partially assembled version )
- 1 x Dual channel knock sensor interface
- 1 x iButton reader & 1 x iButton interface chip & 2 x iButton
- Is this still supported by the software? How is this connected?
- 1 x EGT input amplifier
- 3 x Injector or WBO2 heater driver
- Originally injectors are all connected to the one and same output. Wire all injector to it's dedicated output (inj. driver channel). It's easy to drive them in sequential or 2 banks just by changing injgroup configuration (h table "injector sequence")
- 1 x Wideband O2 sensor
- 1 x Wideband connector
- 250kPa MAP sensor
- Ignition driver
- Are these needed with the ignition coils in question?
- Anything else?
Next thing to do:
Finalize the SHOPPING LIST and make order.
- Is there a tool for making wiring diagrams?
- You can make wiring diagrams like this
- with corel draw just download the image file * http://www.vems.hu/files/PeterJensen/wiring/36-1_diagram_vems.cdr
- Also you need corel draw you can download the program from the *internet