As I need to have a few projects going at the same time I have been experimenting with a hydrogen generator.
It consists out of a set of stainless steel plates that are submerged in distilled water with some potassium hydrochloride (KOH) mixed in the water to get the current flowing. Connected to a 12 volt battery it starts to generate Hydrogen gas which then flows into the engines intake.
This will improve the combustion process and save fuel( look on Youtube under HHO generation)or so the story goes.
I have made a few different models but am in the process of testing them to see if indeed it will improve the mileage.