The car
The project car is a BMW E30 325iS with a M20 3.0 litre stroker engine and T04E turbo. The stock Motronic 1.3 system is not good enough for this engine, and it has been decided to install a Genboard.
Many details will be the same as for the installation of MembersPage/GergelyLezsak.
Engine details
Some of these things are still not decided upon:
- Engine: M20B25 , 6 cyl inline, 12 Valves, SOHC.
- Primary trigger: Stock 60-2 VR crank-trigger.
- Ignition system: Single coil, mechanical distributor.
- Idle control : Stock solenoid, two coils - only one used.
- I heard that both coils must be used, "A" powered to decrease opening and "B" used to increase it
- Fuel injectors: 32.5 pound
- TPS: Yet to be determined.
- IAT: Yet to be determined.
- CLT: Stock coolant sensor has NTC curve 2.5kOhm@20C. (NTC's are normally rated at 25C ... not a big difference though)
Issues
- TPS needs to be converted to potentiometer-style for best result. Resistor network cold be hacked together to get three unique positions or a modern TPS could be mounted.
- There is no stock IAT with the AFM gone. It could be custom made with a NTC thermistor (found in Webshop) or maybe a commercial GM/Delco IAT sensor ($16 at Summit Racing).
- Fuel injection needs to be sorted out, this depends on keeping the stock harness or building new one which wires to separate injector drivers for each injector.
Genboard wishes and details
The assembled unit should be configured like:
- Primary trigger: VR sensor / 60-2 wheel
- Secondary trigger: Currently no cam sync, but prepare the board for Hall.
- Low voltage flyback.
- One channel EGT mounted with flying loom, see below.
- Knock is also mounted for most v3.3 (and for all v3.3 in EU stock at the moment) Yet undecided on this feature.
- Stepper chip is not needed, BMW uses a solenoid valve which can be controlled through other means.
- Deliver with TO220s clamped to case.
Econoseal harness or just connector
- If you can/want crimp, order EC18-wire and EC36-wire.
- If you want receptacles with crimped wires, you want EC36-harness and EC18-harness.
Flying loom for LCD
Is the connector on the loom of type DSUB9 (female) or DB9 (male)? There is often confusion as to which is male and female.
And which pinout is used? The newly proposed one or the old, both found on page GenBoard/BuildProcedures/LCDconnect. The newly proposed one is preferred.
The display that will be used does not need negative voltage for contrast .
EGT conn
- K-compensational cable soldered to the board.
- Together with the small filtering cap (we use 0805) of almost any value (10..220nF probably best) soldered at the connection near the AD597AR chip (bottom of the board, at the place where the K-compensational cable meets the board).
- K-compensational cable attached as a flying loom out through the end plate (rubber grommet).
- K-connector is the rectangular miniature (common), female on flying loom and a separate male connector for later mounting on thermocouple cable end.