I want to turbocharge my BMW 518i E28 M10 engine by using VEMS
ITEMS TO BUY:
- Genboard v3.3
- injector FET 6x
- WBO2 FET 2x
- ignition IGBT 8x
- mapsensor 2.5 bar
- idle stepper moter driver
- econoseal PCB connector 36 + 18
- econoseal harness 36 + 18
- CNC case
- LCD
- tempsensors 2x
- WBO2 connector + sensor
I recommend buying a pre-assembled Genboard to avoid this part of the project, but in case you feel confident with electronics and like the idea of saving some money - then go ahead. I would advice you to fully populate the board with as many fuel injector FETs and ignition IGBTs as you can afford - they can be used for a lot of other things and the minimum I'd recommend is 6xFET + 5xIGBT. That allows you to run a direct-fire (distributorless) setup in the future.
Trigger/ignition plan: MembersPage/MarteleurTim/Ignition
TPS issue
A true potentiometer type TPS is recommended for full use and control. A WOT switch is not much use, it can be used to raise boost target with BoostControl. In MegaTune you configure and calibrate the maximum and minimum TPS values (idle and WOT). You can also set the idle threshold value (1-2%).
Only in some cases do you really need to know the exact position of the throttle plate. You can use a resistor grid with the stock "on/off" TPS, to make three distinct positions/resistance values (idle, in between, WOT). It has worked really well on this car: MembersPage/MattiasSandgren/BmwSevenTwentyEight
The basic idea is to connect the TPS In (EC36-1) to a pullup resistor towards +5V (EC36-28) and a pulldown resistor towards GND. The pullup resistor is shorted by the WOT switch (raising TPS In to +5V) and the pulldown grounds the signal. To protect from a short (should never happen), connect a resistor between GND and the pullup resistor and Idle-switch so that there is a minium resistance to be met between +5V and GND at all times. Use 1K resistors, or similar size.
[A drawing of the circuit used with the stock TPS]
Coldstart
Q: How will I control coldstart issues?
- Afterstart enrichment. Afterstart enrichment has a cold value (config.awev=1D for +29% at -40C) and a scaler (config.awev_temp_scaling=A0 for 160/256 * awev) so it's downscaled at high temps (above 71C)
- warmup enrichment
- To avoid having too much air enter the engine when it has warmed up, get a bipolar stepper valve or an idle air solenoid from a Motronic car and do like this: MembersPage/GergelyLezsak/IdleControl (it's still an experimental setup, isn't it?) GenBoard/Manual/Config/IdleControl
Q: should I use the solenoid type or the mechanical type from the Ljet? What is the easiest and most reliable?
[Picture of Auxiliary air valve (usually L & K-jetronic)]
or this one from the motronic
A: I'd use the Motronic to get the most control, it's a bit experimental but it would be neat if you could get it working properly. Gergely is working with this one on his BMW. You can find Gergelys work here: MembersPage/GergelyLezsak/IdleControl
If you want to avoid the guesswork you can use the older bi-metal "Auxiliary air valve", it does a good and reliable job and is activated as the "fast idle" valve, and shuts off at a specific temperature.
Q: When I use the Auxiliary air valve how will the electrical heating be ensured?
A: There are two types of auxiliary air valves, most are electrically heated while a few early types are only heated by the engine block/head/coolant. When the valve is cold the blocking plate rotates or pivots to allow bypass air, when it's warm the blocking plate closes the opening. Both types have a bi-metal arm that moves the blocking plate and that is what is influenced by both engine temperature (by being bolted to the head usually) and the electrical heating on newer models. The engine temperature is the major factor on a warm engine, the electrical heating has little merit here and is usually controlled by the thermo switch usually found on the thermostat housing of engines equipped with these. You can use the default EC36-pin3 (P259, 4) to ground a relay that in turn delivers power to an electrically controlled auxiliary air valve.
Assembling V3.3
Q: Can I follow the same instructions as for V3.2 for connecting powersupply and connectors for serial cable etc...?
A: Yes, only the trigger connection is different, the 2x3 pin header now misses the south-east pin. Connect the northern middle pin to the north-east pin to get the primary-trigger forward.
- Probably close, but someone has gone through the trouble of making a [V3.3 User Guide]
Q: Do I have to connect a connector onto the 3pin header which I soldered on the board for the serial connection? Or is this done through the EC18?
A: You can do it either way. If the box is mounted in a location that makes it hard to reach in there to connect the serial cable, it is a good idea to permanently mount a serial port in the car and wire it through the EC18-connector. I would recommend a custom cable using a 6.3 mm phono plug (for audio use), it can be bought through the webshop.
Power Up: MembersPage/MarteleurTim/Powerup
OK LCD working and no damage so far as on misconnecting the LCDheader.
PS2 keyboard
The JP_PS1 headers is the one in this picture, to the left of the Atmel. Pin 1 is the one furthest from the EC connectors and also farthest up in the picture. Documentation on this is under reconstruction, I can't find the old page anymore. //Mattias
JP_PS1 | Mini DIN6 | Function |
1 | 4 | Vcc |
2 | 3 | Gnd |
3 | 1 | Data |
4 | 5 | Clock |
SOLDERED THESE COMPONENTS ON V3.3
1. Flyback lead see pic: [flybacklead]
2. From Rescue kit1 the inductor marked 1R5 must be soldered Between A&B.
If a fused power supply is being used then a wire must connect 1&2, otherwise a fuse link must be used. see http://vems.hu/www.vems.co.uk/VEMS/ConnectingPower.htmlpowerconnections
3. EC18 + EC36 connector
4. 8 IGBT's + 8 FET drivers
5. MAPsensor
6. PS2header + connector
7. LCD Header + connector
8. Serial header + connector
9. D37 Transient supression diode [diode mounted]
10. solder JP2 & JP7
11. solder R30=2k7 pullup resistor
- Tried testing channels with mdh command in terminal
- mdhd7 or others (like mdh87, mdh97, mdhc7 ?) are not giving a ground signal to an attached LED.OK! This was exactly the problem. I connected a relay to pin 15 and +12v and it clicked when mdhd7!
- exactly write what you do and measure, including
- the used ECxx pins (see GenBoard/Manual/DigitalOut/Table )
- DVM mode, and reference used for measurement (20V, measured with respect to +12V in this case)
- measured values
- exactly write what you do and measure, including
If there was no torture (like running injectors without GND5 or flyback), the P259 should work. Thanks Marcell. I thought that those channels give an groundsignal for a led too. But this isn't the case.
Q: Can I test the coil output with a relay?
Q: How can I assign my 4 injectors to a known channel which I can test with a mdh command? I've read the digitalout section but this is very confusing for me.