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Originally Posted by oil pan 4
The vehicle its self is 30 year old technology. So no.
If fuel vapor is the way to go then why has the fuel induction element been moving ever closer to the combustion chamber?
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Fuel mixture control has more benefit than fuel vapor in the immediate applications of need. Thus, throttle bodies gave way to port injection and then to direct injection. But, once injected directly into the combustion chamber, gasoline fuel has a tendency to form soot particulates. Now you are back to square one, with loss of efficiency and greater emissions. Some manufacturers are now exploring duel fuel deliver with both port as well as direct injectors to gain the benefits of both. I also pointed out in another thread that the work by companies such as Orbital of Australia has lead to manufacturers using air assisted injectors to gain even more fuel atomization. The next step is what pgfpro is suggesting - hot air assisted injection - to gain as close to a vapor state as possible while retaining the advantages of digital fuel injection.
This does not mean simply reaching a vapor state and feeding it into the engine will gain you fuel economy. I have touched on that with discussion of a high enthalpy engine. Enthalpy is a fancy word for the energy contained in a system including the work lost/gained by that system. This includes heat, pressure, temperature and kinetic energy as well as the internal energy of the gas molecules. Anything that gains you increased enthalpy before the combustion starts allows you to extract more work from the system.
The above, all makes more sense when you start going down the list of things that we already know help an engine's efficiency.
Higher compression increases the working fluid pressure, and gains us more efficiency.
A warm air intake gives us more heat and more efficiency - all else being equal.
An engine with large amounts of swirl and tumble in the combustion chamber design is more efficient than a lazy one. This is the kinetic energy addition to your system ( working fluid ).
Internal energy concepts can be more involved and complex, but let it be said that the vapor state is at a greater enthalpy level than fuel drops that will irreversibly absorb energy to reach a vapor state to completely burn. And trust me, modern engines burn 98% of the gasoline in the combustion chamber so a vapor state is not the issue. It is the loss of enthalpy in the forming of the vapors within the combustion chamber. A fuel already in vapor form does have an enthalpy advantage over a fluid form if only by a few percent.
So is it worth it to fool with vapor engines? I think so. If you add in all of the above and the thermochemical acceleration of the combustion event (combustion contraction).
Your work with turbo charging, pgfpro's build, dustyfirewalker's, and even soulcrusher's - they are all related by the idea of higher enthalpy combustion. In the deleted thread was a post I really want to add to the list - the build of the Metro engine with a Smokey heat engine induction system. Who ever that was, get your build up on a thread!