MembersPage/MarteleurTim (2015-01-01 07:00:00)

I want to turbocharge my BMW 518i E28 M10 engine by using VEMS

I live in Belgium

LCDincar2.JPG


Engine specs

Initial completely stock engine, in second stage-->(turbo, inj, intercooler...)


ITEMS TO BUY:

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?

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

[Idle air solenoid]

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.

[Picture of Genboard v3.3]

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_PS1Mini DIN6Function
14Vcc
23Gnd
31Data
45Clock

[PS2header]


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