Hi Evan,
I could not log on to the site and update the progress for a long while and I will be happy to explain/answer as much as my English let me. So, do not hesitate to ask whatever you want.
For the engine position sensor, I've got the pulse from the Ignition Control Unit. I've used an insulated cable (ground wire is coaxial over the live wire) in order to eliminate interference.
Only load on the engine is measured with the TPS. You're right, the black block on the left injector body, which the body belongs to an R11xx BMW.
There's an air temperature sensor attached between the two nozzles at the top cover of air filter.
Engine temperature sensor is located under the air filter. I've dismantled one of the air box screw that keep the box attached to the body and inserted a small sensor with the same thread.
I've a "portable" O2 sensor which can be attached to the exhaust exit of the muffler. This sensor reads the fuel/air ratio on the exhaust and corrects the mixture amount via the custom made control unit.
The unit linked at e-bay is only a processor. We've designed and have it produced a control unit which has the said processor installed. Later on found some errors on the PCB and corrected the faults. I need to re-design the PCB and have it manufactured again. Primary design of the PCB is here :
http://www.flickr.com/photos/94158592@N03/8570979497/in/set-72157633036229410My friend, who is an electronic engineer wrote the whole program. All the settings can be modified with a laptop. Even we put 3 tiny switches on the PCB which can be programmed and used to change the settings. For example, increase/decrease fuel level at various RPMs.
I hope I could answer your questions.
Cheers,
Ibrahim