http://www.rexresearch.com/ogle/1ogle.htm





I came across this watching a documentary about Oil.

How legitimate is this ? Has anyone been able to reproduce this ?

It’s possible, but I’d have to throw a few big caveats on that.

First, I can’t seem to find any controlled experiments or tests for his system. Something like running the engine in isolation to the car with carefully measured amounts of fuel, Purging the entire system with a nitrogen flush to ensure no extra fuel left over then running the tests, or an energy flux analysis at all inputs and outputs to determine the true system efficiency.
The only tests I can find referenced are demonstrations Ogle conducted for reporters. None of them sound very controlled and none of them look like they were conducted by an impartial 3rd party, which opens up the opportunity for bias or tampering.
Most of his demonstrations sound like they follow the same theme. Drain the tank, pour in “about 2 gallons” then drive the car for along ways without stopping. There’s no mention of any precise measurement of the fuel put in the tank, how much was actually used, his driving method, any impact on the performance of the car (how was engine power effected), or any mention of a purge of the system before starting; particularly important if you’re trying to accurately measure how much vapor is in the system before you start.
Additionally, all of the reports of experts reviewing the system are stated the same way. “Automotive Experts” reviewed the system and could find no hoax. Any time you see an “Expert” referenced but they don’t tell you who the expert is or what there particular expertise is, that a big red flag

The biggest problem though is the intent of his “Black Box”
The whole point of the vapor fuel system was to increase the burn efficiency of the fuel (make it burn more cleanly and efficiently). But that completely overlooks that real reason cars don’t get good gas mileage. Most modern engines burn the fuel extremely efficiently; they just have a hell of a time converting all that energy into useable mechanical motion. Even if you burnt the fuel with perfect fuel air mixture and 100% efficiency, which ostensibly, is what Ogle’s system was supposed to do, you still wouldn’t be able to pull 100 mpg out of a standard 4 stroke because it wastes too much of the available energy converting it into motion.

At best it looks like the guy made an engine that ran very lean, sucking a lot more air then fuel. With that kind of setup you’d use very little fuel to run the engine and it could run along time, but the engine would be very low on power. That’s how most of the standard drive super high MPG cars do it today. They just sip a little fuel at a time, but they barely have any acceleration, and their top speed is extremely limited.

There's another (really BIG) downside you forgot. Running lean causes the heads to run hot and will eventually burn up the valves and guides.

I tend to be skeptical of any system promising magical fuel economy numbers. Having a patent is no guarantee the mechanism actually works.