I don't see any evidence that HHO was created and collected. How do they know this was made? Did they do spectroscopy on it? Do they have predicted ab initio type calculations for it's structure and spectral properties? In all honesty, I think HHO may actually be a physcially possible species, but it's likely some type of unstable intermediate species that would rapidly, on the picosecond time scale, rearrange or dissociate into something else. After all, I've been to presentations on the formation of H3. But these types of chemicals aren't something you can accumulate and store. Frankly, the guy is full of BS on his water car project.
http://hytechapps.com/index.html
Check the scientific paper that goes with this. The guy who wrote it can only postulate on what's happening, and yes, there are a lot of GCMS charts included.
I cannot help but wonder if it's not related to something on another weird site:
http://www.blacklightpower.com/
Truth outs. So all we really have to do is pop popcorn and enjoy the show.