What if anything can to be done to run a 2006 HCH II on ethanol ?

I dont really know. Is ethanol same as alcohol? If it is, then would they check your ID for a fill-up? Would the government require gas companies to add additives? Sorry for my lack of knowledge. Not trying to be funny or anything.

Probably, the gas tank would have to be replaced, since ethanol is pretty corrosive to many materials. The ECU would have to be reprogrammed, the fuel injectors would have to be replaced with bigger jets, as it takes almost twice as much ethanol to produce the same energy as gasoline. Seals in the engine and fuel system may have to be replaced with different material. Doesn't sound like a do-it-yourself kind of project.

The manual says E10 is the max from the factory.

Ron in SoCal

Saving the Dinosaurs . . .

Even though it may take as much as twice the fuel to produce the same MPG.... we are forgetting that you can make the engine work much better by raising the compression ratio much higher and take advantage of the gain that said compression ratio would give.

You could probably get away with a fairly high % of ethanol without doing anything-maybe 20-30%.

Heck, it would almost certainly run on 85% ethanol. I don't know how much power you would lose-not sure just how much excess volume capacity the injectors have.Like Kephra says-you would have to pump about 45% more volume per unit of time to get the same peak hp. There might not be that much reserve in those injectors.
It would take a while-maybe years(1-2) for 85%ethanol to destroy whatever seals are susceptible to it. Of course,manufacturers have to make the seals good for 10-20 years of 10% ethanol, so you can figure about 1/9th of that for 85%.
All in all, it isn't worth trying on a new vehicle.In 5 or so years get one with 100,000 miles and retrofit it.Luck,Charlie

So in summary,

I would recommend you go with the 10% MAX Ethanol (E10) as the factory recommends (posted above).

Others are also correct that the ECU would need to be remapped and programmed and also not only would you need a new gas tank, but new hoses, lines, new seals and basically a new fuel system including injectors. Basically if the system is not designed for E85, then E10 is the maximum (same percentage for other additives such as MBTE (no longer used)) and such.

You can bet that there will br retrofit specialists in the future.

I have heard that certain 'domestic' engines are more easily adapted to ethenol because of the larger tolerences in the engine. Don't know if there is any truth to this however.

I have never heard more conjecture and guessing in any other thread...

http://en.wikipedia.org/wiki/E85

Read up. There is plenty of information there to answer all of the questions posed in this thread.

Alabaster Silver HcH

Thanks for the Wikipedia link. That thing is always usually very accurate and quite detailed.