Popular Science magazine awarded Bruce Crower with an invention award for his six stroke engine, covered in The Kneeslider back in February of ’06. Crower, founder of Crower Cams, retired from the company some years back but like many inventive types, he never really retired in the normal sense, he just kept tinkering and inventing because that’s what he does.
The six stroke was the result of his thinking about recovering some of the energy normally lost as heat during a four stroke engine’s operation. By injecting a bit of water after the exhaust stroke, steam is created which expands rapidly and creates another power stroke. The exhausted steam goes to a condenser where it once again becomes water and is recirculated for another trip through the engine.
His engine is called the Steam-O-Lene and he calculates it increases a gas engine’s efficiency by 40 percent, a diesel even more. What I like best is their note that development costs were about $1000 and it uses off the shelf parts. He’s waiting for a patent then he’ll look for a larger company to develop the idea and maybe take it to market.
Who says you can’t invent anything in your garage anymore?
Link: Popular Science
Ryan says
I for one would love to see more of this type of thing. I have often wondered how an ’07 Chevy Corvette can get 505 hp and 21 mpg (according to Chevy.com) and my 2.0 liter I4 can only muster around 30 mpg with its 130 hp.
The other thing that I find odd is that the 2006 average fuel economy in the US is around 21 mpg and a ’08 Ford could get 25 mpg (that’s a 1908 Model T by the way, almost 100 years ago)!
Now, I love big horsepower numbers, fast cars and bikes as much as anyone and I think that people should be able to have them if they so choose. I just wonder why, if 505 hp and 21 mpg is available now what are the big hurdles to offering cars getting say 150 hp and 60 mpg from just internal combustion?
p.s. I know the Toyota Prius is an option as a hybrid
Mark Koontz says
I can assure you that when a Corvette is making 500 hp that it’s not getting 21 mpg. Most cars, regardless of their max hp, will put out simular numbers when going along the same road at the same speed.
Its all about how much hp is needed to push that car at that speed…[Around 20 hp.] And the variables there are wind friction, engine/driveline friction, and to a slight degree, engine efficientcy. So the ‘Vette has less air friction and more engine friction (more cylinders) and so it tests close.
BTW- There are no hidden 90 mpg carburators out there either… Because the fuel-to-air ratio is pretty set.
Ryan says
Mark,
That does make a lot of sense. I guess that would be why hybrids are the only realy 50+ mpg option
Thanks
todd says
It doesn’t answer why motorcycles don’t get very good mileage. Well, mine do… My GB500 gets 50-60MPG depending on how I ride, my 90cc two-stroke twin gets well over 100mpg.
It’s complicated. If an engine was designed for peak efficiency (peak torque) at 5,000 RPM and most of your speed focuses around that RPM you will have good MPG. Remember what Mark said, it only takes a certain amount of power to move down the road at a certain speed. In the case of a motorcycle, 15HP will get you around 75mph. A 250cc engine producing 20hp probably puts out peak torque at 15hp and is probably geared for 65-75 at that peak, hence excellent economy (Ninja 250 gets approx 70mpg).
To put it in simple terms, the closer your engine is to making peak torque at the speed you’re riding – in its highest gear – the better your mileage.
Most bikes available now produce gobs of torque at fairly high RPMs (say, 8k) and are geared for top speed (say 160mph). Chances are the engine is nowhere near its peak torque RPM at highway speeds unless you run in second gear – at which point you cannot provide enough throttle to achieve maximum torque and efficiency.
-todd
-todd
Trey says
I’m amazed that so many people forgot the “econo-box rollerskates” we had about 15, or so, years ago that got 50+ mpg. They exist, but we don’t want them… E85 is a lame joke. Hybrids are a bandaid on a gaping chest wound – at best. Electric is promissing, but it’s gonna take more time to be practical.
But, alas, the six stroke is brilliant – Crower took a few good ideas, played with ’em a bit, and came up with a smart concept that works!
Trey
Sean says
Todd, I own the 250cc version of your GB500, the CBX250F. I get 200km+ out of 6-7 litres of 98, which is about $10-12 in NZ. According to Google, 7 litres is 1.84920436 US gallons, and 200km is 124.274238 miles, resulting in 67 miles per gallon (give or take). Now, enough of this MPG crap. This engine is very, very cool. Not supposed to be a pun or anything, but I like this a lot. I’ve always wondered how to harness the heat that sends water hissing up off my cylinder, and this looks to be a smart way. Peroxide would be a good way to get maximum efficiency, and varying the water to fuel stroke mix would be a great way to achieve maximum efficiency too. It would work better in a 2 stroke engine though, not a 4 stroke because of the dependency on completing the 4 combustion strokes. Damn, but is this a cool idea.
Dodgy says
I’m not knocking Mr Crower, but this has been thought about for years…
I hope he has it right!
One concern of mine is that water is a very effective scrubber, and the damage it could do by removing the oil film from the bore would be nasty.
Here are some others I found while looking for one I saw years ago:
http://www.freepatentsonline.com/5000003.html
http://peswiki.com/index.php/Directory:Cyclone_Technologies_LLLP
http://www.halfbakery.com/idea/internal_20combustion_20steam_20engine
Jeff says
This is a fantastic idea. I have long thought gasoline/diesel-steam hybrids to be a great idea. But one problem that I see is the rapid expansion and contraction of the surfaces that come into contact with the injected water. I think it will reduce engine life damage the cylinder walls and piston. I wish the best of luck to Mr. Crower, and I hope to see this engine in mass use someday, but it seems that he will have a number of obstacles to overcome.
Just my 0.02
george says
Rehashed old idea that the original patents have expired on.
These things were bandied about 50 years ago, and no one could make em practical because of lubrication, corosion and volume problems.
Yes, it will work, .. for a while.
With all the computer control, advanced materials and lurication tech. we have today, why does his engine look no diferent than the ones they tryied back in the thirties?
I’ve been following Mr. Crowlers work on this for a while, and I have thus far seen no evedence that he has solved any of the problems inherent in these engines.
How about an award for developing misleading hype for investors?
Dodgy says
You know, I thought of an easier way of using steam to improve the efficiency of IC engines, which could be (relatively) easily applied to existing equipment.
How about running all the ancillaries (alternator, water pump, air conditioning etc.) from a steam engine which simply uses lost heat from the exhaust?
By having a flash boiler set up in this way there are no moving parts like a turbo in the hot gas stream. A flash boiler coil could simply be wrapped around existing pipework.
scott says
what about the rapidly expanding and contracting metals in the engine wouldnt this greatly compromise reliability and durability ?
dxg says
Another thing to note is the difficulty in reaching a better MPG.
Whilst some hybrids claim 60MPG, to raise that figure to 100 would require an extremely clever design, or many compromises.
In reality this may mean that the car may take 30 seconds to reach 60 miles/hour and go through 10 gears getting there. Not exactly ideal..