The discussion centers on the feasibility of achieving 100 miles per gallon (MPG) with a 427 cubic inch V8 1970 Ford Galaxy through fuel vaporization techniques. The video by "Driving 4 Answers" suggests that fully vaporized fuel burns more efficiently, allowing for a leaner air-fuel mixture of 40:1 compared to the conventional 22:1. However, participants agree that while vaporization could theoretically improve fuel efficiency, it results in significantly reduced engine performance and requires a large displacement engine to maintain adequate power. The conversation also touches on the historical context of vaporization in stationary engines and the challenges of modern emissions regulations.
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If there was no unburnt fuel at all, we wouldn't need catalytic converters.tech99 said:I am not sure we see unburnt fuel in a modern spark ignition engine, so I am doubtful abut the advantage of pre-vapourising the fuel.
Absolutely brilliant reply, Jack!jack action said:If there was no unburnt fuel at all, we wouldn't need catalytic converters.
Yes, but there is still a twist here. The author does state that running on vaporized fuel alone would have terrible performance. So modern engines set up with propane or LNG would be tuned differently, and not be talking (supposed) advantage of the lean ratio.russ_watters said:I think this is a pretty good reason to believe there is next to no benefit:
Just being liquid vs vapor doesn't say much - it doesn't change the amount of energy available by more than a few percent (e.g., you could preheat a liquid fuel). In order for there to be much of a performance hit due to the fuel being liquid, it would have to be not burning or burning very late, and that just isn't happening.
According to the Wikipedia article, it might sort of be the other way around?jack action said:If there was no unburnt fuel at all, we wouldn't need catalytic converters.
So reducing carbon monoxide. And...These "two-way" oxidation converters combine oxygen with carbon monoxide (CO) and unburned hydrocarbons (HC) to produce carbon dioxide (CO2) and water (H2O).
reducing NOx - but some unburnt fuel is needed for the conversion. I think you can have very complete combustion, but with high NOx levels. So that would be a problem, and the 'solution' is - more unburnt fuel! Well, engineering is always a balancing act, right?"Three-way" converters, which also reduce oxides of nitrogen .... three-way-converters require fuel-rich or stoichiometric combustion to successfully reduce NO<em>x</em>.