This is my 1989 Volkswagen Golf MK2 project car that I'm planning to run FreeEMS with:
.. pic here ...
It now runs on microsquirt module based EMS and has been running ok. The idea to switch from a working system to FreeEMS is to experiment new things and build a base for future ideas. The S12X MCU looks promising and because of the MS3 closed source politics my DIY spirit has a little more love on this project.
The car is only used in the summer and I attend several trackday events during the season. Only the shell is original. Axles, suspension, tank, etc parts are from a MK3 VR6. 12" brembos at front and VR6 disks at rear. Koni/Eibach shocks and springs...
The current engine is a N/A street tuned. Using it as a testbed for my EMS fiddlings to get things right. I have a turbo engine in the works and is halfway finished.
Current engine:
- 1.8 GTI block with 1.6 AKL pistons (balanced with rods)
- 2.0 MK3 8V GTI head
- Siemens "Simos" sequential injection as base setup
For FreeEMS I'm planning to use the ELMicro CardS12 MC9S12XDP512 module:
http://elmicro.com/en/cards12.html
I will be adding different small breakout boards to get everything connected. It would be tempting to use the MS3X expansion card for this, but it still don't have enough A/D inputs etc to use it as the only breakout and I HATE the d-sub connector.
For injector outputs I'm already using this on my MS setup:
http://www.diyautotune.com/catalog/diyp ... p-386.html
So I could have two of these to run the injectors. For wasted spark ignition I could continue running two BIPs.
The triggerwheel is a 60-2 at the crank and because the old block didn't have a place for the VR sensor I had to relocate the wheel outside of the block:
The hall sensor for the cam is at the distributor. Although I have replaced the distributor cap with wasted spark coil and the sensorwheel is spinning under it.
For these signal inputs I could use a double LM1815 board or other dual VR conditioner. Not sure if the cam hall-sensor can used with these?! There is a board available at my "local" online store:
http://autotune.fi/data/th/c_at-vr_doub ... 5c_2a8.jpg
Most of the sensors I use are just standard bosch, MPX4250 for the MAP and Innovate LC-1 for AFR. I could roll my own A/D conditioner board for all A/D needs if there isn't anything ready? This shouldn't be too hard...
The TPS and Idle are a little trickier because of the "semi drive-by-wire" type bosch throttlebody (same as in 1.8t, etc). TPS has two potentiometers and needs to be reverse connected (+5V to GND and GND to vref) to the other one to work as 0-5V fullscale. This works ok in the MS.
The Idle has been impossible to get working using the PWM output. I have experimented with different frequencies etc and it opens the plate a little and creeps up until its fully open. So, there is no control what so ever... Oldschool PWM idle valve is working ok, but it feels a little oldfashioned and hate the extra plumbing... Anyone have any insight on this one? Is there a h-bridge of some sort to switch the polarity back and forth? I'm not planning to run any AC so all I need is the coldstart idle to work.
For idle PWM (old valve for the time being) and fuelpump relay I could use this simple board:
http://autotune.fi/data/th/c_at-io.jpg_35c_2a8.jpg
So, we'll see where all this leads, but I'm feeling quite confident More info when things get a little further...