Opposed Piston - Opposed Cylinder engines.

[53k]

From an email I received this morning. I live in fear of posting something that was posted before, but I couldn't find anything about them and I found them interesting enough to gamble.
It's actually a video, not an article and it's well done.

"Here's a really good article on new "Opposed Piston - Opposed Cylinder" engines. Don't confuse these with "horizontally opposed" engine designs. There is only about 50% similarity - the pistons operate in the same plane. Check this out and see if you learn something totally new. I did! http://www.cnet.com/roadshow/videos/car-tech-101-opposed-piston-engines/"

[doug]

That is interesting and generates a lot of questions. Thanks for providing.

[stall]

That is interesting and generates a lot of questions. Thanks for providing.

Don't worry, the Forum posting police take vacations in the Winter, Lol

Very interesting BTW, thanks
Murray

[Skip Lackie]

Large opposed piston engines were built for many years by Fairbanks-Morse, and powered hundreds of US Navy submarines (until the Navy switched to nuclear power). Based on that success, FM built diesel locomotives with OP engines from the 1940s until 1963.

[jclary]

Large opposed piston engines were built for many years by Fairbanks-Morse, and powered hundreds of US Navy submarines (until the Navy switched to nuclear power). Based on that success, FM built diesel locomotives with OP engines from the 1940s until 1963.

As in "Nothing New Under the Sun"...this, and similar concepts, have bounced around, in engineering thought, for years. With all the supposed advantages of the ones presented in this video, it would have been interesting to view it with the (late) Felix Wankel. My guess is he would claim these designs are too complicated, have too many moving parts, and too many changes, of motion direction, for desired effect.

His rotary engine is a great concept for combustion engines, and viable to the point that most major corporations seriously investigated building a version. Just as Toyota's Prius has legitimized a marketable electric...Mazda did that with a rotary engine. I believe it is a great concept, but from my limited experience, it is not as clean burning or fuel efficient as other more complex combustion engines. The efforts to make it comply with emission standards has resulted in off-setting its mechanical simplicity.

The above impression is purely my assumption, from my limited observation, and experience with an early version of a Mazda RX7. Like us Studebaker Nuts, there is a group of rotary engine fans, who passionately pursue, collect, and enjoy (almost to cult status), and defend, rotary powered vehicles. Like all concepts, there's good and bad. The good is new businesses pop up to support the technology. The bad...folks like us have difficulty finding obsolete parts for old technology.

[christophe]

The Napier Deltic engine.

[dictator27]

As jclary says, there is nothing new about this. In the early days of the automobile France was the leader in automotive development and this was no exception. French automaker Gobron-Brillie produced vertical opposed piston 4 and 6 cylinder gasoline engines for years, beginning in 1898.

wkikpedia.org/wiki/Gobron-Brillie

British truck maker Commer produced a horizontal three cylinder two stroke opposed piston diesel engine called the TS3 (commonly referred by British truckers as the "knocker"). The noise these made puts a Detroit 2 stroker to shame!

youtube.com/watch?v=x2U475ab3f8

Terry

[48skyliner]

"Just as Toyota's Prius has legitimized a marketable electric...Mazda did that with a rotary engine. I believe it is a great concept, but from my limited experience, it is not as clean burning or fuel efficient as other more complex combustion engines. The efforts to make it comply with emission standards has resulted in off-setting its mechanical simplicity."

Starting in 1979, I owned a lot of rotary powered Mazdas, including an early style GLC sedan which I converted to the rotary. I never owned a rotary powered car that got more than 20 miles per gallon, and if driven hard, it was much worse. The combustion cycle is just not efficient, and can never be competitive with a modern piston engine. Now that we have variable valve timing and computer controlled ignition and direct fuel injection, the modern piston engine has gone far beyond anything that is likely to be achieved with a rotary. It was a great idea back in the 70s and 80s, but its time has come and gone. And yes, their is definitely a cult of rotorheads, some of whom hang out in my garage, but they all approve of my Skyline powered RX-7.

As for the complexity of the opposed piston engines, they are pretty simple compared with the sleeve valve aircraft engines that the British built during and shortly after WWII. The Napier Saber 24 cylinder engine was fantastic, with two flat 12 engines, one on top of the other with the crankshafts geared together, used in the Hawker Typhoon and Tempest fighters. I once read a fascinating little book entitled "the power to fly", which told the amazing story of the extremes that Rolls Royce went to in order to sabotage the Saber when it entered service, using their influence to make sure it had poor parts availability and no trained mechanics. When I was in England a few years ago I tied to find a copy and no one in the book stores had heard of it, not listed in the catalogs. My guess is that Rolls sent people around and bought up every copy, cleaned out the libraries, etc. I recently found a copy listed on eBay for $700.

The Bristol Centaurus is a radial sleeve valve engine used in the Hawker Sea Fury, the last piston engine fighter ever developed and produced, shortly after the war. A few were raced at Reno, not terribly fast, but very quiet.

[Hallabutt]

In addition to Navy and Coast Guard using the massive Fairbanks-Morse diesels they were also used in train locomotives.

[jnormanh]

Starting in 1979, I owned a lot of rotary powered Mazdas, including an early style GLC sedan which I converted to the rotary. I never owned a rotary powered car that got more than 20 miles per gallon, and if driven hard, it was much worse. The combustion cycle is just not efficient, and can never be competitive with a modern piston engine. Now that we have variable valve timing and computer controlled ignition and direct fuel injection, the modern piston engine has gone far beyond anything that is likely to be achieved with a rotary. It was a great idea back in the 70s and 80s, but its time has come and gone. And yes, their is definitely a cult of rotorheads, some of whom hang out in my garage, but they all approve of my Skyline powered RX-7.

My wife owned an early RX-7, and what you say about them is all correct. I don't think I'd want another, but...

A friend bought a new '93 RX-7 twin turbo. She let me take it for a drive. From a standing start I crossed a small bridge about a quarter mile away, at just over 100 mph. It got a little light over the bridge, and spun both rear tires. Woooo-hoooo. Not bad for 80 cubic inches.

I also managed a street drag race with a Kawasaki Z1. At 60 mph, the Kaw had a ten foot lead. After that he disappeared in the rear view mirror.