The schematics that I'm using make use of a dual electrolysis method using a coil and an electrode. The one produces a much slower burning gas that should be easier on the pistons.In any event, experimenting with "water fuel cells" is potentially extremely hazardous, both to the experimenter in the short term (fire/explosion hazard), and the engine over the long (or even short) term. Dramatically increasing the speed of the flame front by introducing a stochiometric hydrogen/oxygen mix will hammer the dickens out of pistons & rings, cylinders and rod/main bearings, likely leading to premature failures - even if the ignition timing is significantly retarded.
Its not that much totally unburnt fuel comes out of the exhaust, but there are alot of intermediate molecules that aren't totally burnt. If you think about the chemistry of an internal combustion engine, under ideal conditions, the only end products should be CO2 and H2O. As such, there are always a vast number of other carbon compounds excreted from the engine due to the inefficiency of the process.Point of clarification, if you please... Are you claiming our cars spit unburned fuel out the tailpipe? If so, please document. If not, please clarify.