The real key to improving fuel economy is efficiency, which brings us to other items that aren't as difficult to obtain as hydrogen, like raising octane ratings. A simplified explanation follows. The higher the octane, the more efficient the combustion. The slower the burn, to a certain point, the higher the octane. Water vapor slows the burn and increases octane. On a foggy day there is a higher percentage of water vapor in the air, increasing horsepower. The horsepower increase on a foggy day is due to increased efficiency which is due in a round about way to the octane increase. When octane is increased, the timing can be advanced, which contributes to an earlier spark and the opportunity for a longer burn.
Computerized cars, after 1996 in the US, have OBDll compliant computers. Computers, if matched to the right system, will due all the changes. You don't have to advance and retard the timing or rejet the carburetor for different altitudes and conditions because the computer does that for you. With the right system you don't have to do anything to the computer. The computer sensors monitor the exhaust and lean the mixture if the engine is running cool enough. 60% to 80% of the fuel that goes into the engine is used to cool internal parts. Water is about 200 times more efficient at cooling than gasoline or diesel.
I was watching a NASCAR race and one of the commentators made the statement that "all the horsepower is in the camshaft and cylinder head(s)." That statement, in the way it was worded, in not correct. A large percentage of the horsepower is in the camshaft and cylinder head(s), but not all. There's a reason the fuel they burn is rated at 99 octane. The slower the burn, the more complete the combustion.
A engine has to "breathe" to be efficient. Like the human body, if the air ways are fouled or restricted, the human body and the engine aren't capable of reaching maximum efficiency. Water vapor steam cleans internal engine parts. It breaks carbon off the valves and flushes it out the exhaust while cleaning the exhaust system in the process. If water vapor is introduced at the right place in the intake system, it cleans the passages, mixes with the fuel and increases octane. Higher efficiency results in more HP and better fuel economy.
Going back to hydrogen, there is a hydrogen producing system that's as close to free energy as you can get and already on all automobiles. It seems to make sense to use what's available, as opposed to wasting it and expending other energy to produce more. A high priced, high tech vehicle isn't necessary. But, to make everything work at the optimum, you need to have all the information and not just one piece of the puzzle.
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