Posted on 04/29/2008 7:38:08 AM PDT by Red Badger
Researchers in the UK have developed a new kind of engine. It could be called a hybrid, but what it combines is not two power sources but rather two mode of operation: 2-stroke and 4-stroke. The goal is to be able to significantly downsize the engine and get the fuel economy benefits of smaller displacement, but to be able to switch seamlessly to 2-stroke mode when more power is required at high loads and low speeds.
The prototype (seen above) is a modified 2.1-liter V6. After tests at the University of Brighton, it has been found to produced performances similar to a 3 to 4-liter engine, with fuel savings of 27% and emissions reduced by about the same amount.
The next goal of the researchers is to incorporate the prototype engine in a vehicle.
It isn't the first time that this kind of hybrid 2/4-stroke engine design has been looked at, but in the 80s and 90s the technology simply wasn't advanced enough. "According to Ricardo, the only reason the company is able to make a viable system now is because of the software that controls the gas exchange and engine modes."
If all goes well and nothing major holds back the adoption of such a technology, it could make a big difference in the next few years. Of course, the goal is to move away from fossil fuels, but realistically, that will take a while and in the meantime a 30% improvement in efficiency would be welcome (trucks with 2-liter engines, cars with 1-liter engines). No reason why these couldn't run on cellulosic ethanol...
![](http://images.google.com/images?q=tbn:R8sR7daexSBGmM:www.ted-kyte.com/3D/Pictures/Spark%2520Plug.jpg";)
Rest In Peace, old friend, your work is finished.....
If you want ON or OFF the DIESEL ”KnOcK” LIST just FReepmail me.....
This is a fairly HIGH VOLUME ping list on some days.....
2-4 Stroke engine Ping!.........
I drove a 3-liter Geo once. Someone needs to feed that squirrel!
3 Liter or 3 cylinder? 3 liters is a big engine for a Geo!................
3 liters is 183 cubic inches! THAT GEO WOULD fly!.............
I think it’s a 1.3 liter 3 cylinder, or some such.
I test drove a 5 cylinder Volvo over the weekend........Nice!..........
Sounds good.
I don’t believe it is diesel, why the spark plugs rip?
I’ve got a 6 cyl BMW...I win
Greater valve overlap and exhaust gas scavenging in the two stroke mode? Iffen remember rightly, Aussie Ford/Orbital’s wet-sump, TDI-ish two strokes of the mid-90s were a very near miss, but were blocked by their emissions.
I drove one of those over the weekend, too! Very nice car........Trying to fit it into the budget somehow, someway........
I didn’t have time to remove the pic........
I drove a friend’s diesel Dodge Ram 4wd on a long trip. Got 15-18 mpg pulling a trailer........Now I’m jealous.........
I can only badmouth the 3 cylinders I’ve driven: Geo and Precis. The Precis in particular was a POS. The engine was so weak even the AC didn’t work. And that’s unacceptable in Texas.
Used to be, I couldn’t even stand 4 cylinders. Now I’ve made myself drive one from time to time, but I still prefer a V6.
Turbocharging/supercharging still provides an advantage to (relatively) produce performance high altitudes. How about a Diesel engine with both?
Turbocharging/supercharging still provides an advantage to produce (relatively higher) performance high altitudes. How about a Diesel engine with both?
The Volvo Inline 5 cylinder is quite peppy......
A supercharger with an intercooler!......
http://www.autobloggreen.com/2006/12/16/supergen-supercharger-improves-diesel-efficiency/
If I can afford a Volvo, I can afford gas...
It was a used Volvo and a used Beemer I drove..........
My new outboard motor is an Evinrude E-Tec from Bombardier Recreational Products. It is a 2 stroke design that has lower emissions than any of the four strokes on the market. It outperforms them, gets better fuel economy and is significantly lighter, has less than half the moving parts and is totally remarkable in a number of ways. It requires no break in, no maintenance for 3 years and has a 7 year warranty. My friend bought the same boat with a Yamaha 4 stroke of equal horsepower, so we compare everything side by side. He is kicking himself for getting the four stroke.
It does not add the oil to the gas. It injects it directly onto the parts that require it. It literally sips oil compared to any comparable two stroke. It is so quiet my neighbors accuse me of trying to sneak up on them. It doesn't matter how long it's been sitting or how cold it is, it starts instantly and runs smooth and flat right away.
The two stroke is a more efficient design than the four stroke, it just always had so many performance drawbacks. With current computer control, the deficiencies have been overcome. I don't see why the same approach would not apply to automobiles.
Our SIL wants a beemer. Are they all that? A lady we know said after 100K mi. the repairs are astronomical.
Name a car whose isn't. BMW's in the long run are very well engineered, and if properly taken care of, maintenance wise, and not driven by lead footed teenagers, then they are good or better than many other cars. The one we were looking at was a 2000 with 75k miles on it and it really was like brand new. Even the headlight covers were clear........
I was looking at one that was a 98 and had 100K for $7500. The guy told me he could have the maintenance reports in 2 days, but I didn’t call back. It was spotless white on white.
This one was for sale by the BMW dealer, so I’d imagine it had been preened to the max before putting it on the line. But still, it was a cherry!.......
The only time we had pricey repairs over 100K mi. was the Town Car. Aid bladders and brakes = $1800, rear only!
Come to think of it, we don’t keep them that long as a rule.
The BMW I found was for sale by an import repair specialist so I imagine it was in fair shape, as well.
Aid bladders?.......they come with those now?...............;^)
3 liters is 3 business cylinders
[blush] That was supposed to be AIR bladders...
[/gasbag...]
My 1996 Geo Metro (Suzuki Swift) had a 1.0 liter engine. I got 44 MPH on the highway at 65-70 MPH. The car was a dream to park. I just had to watch out for the stampeding herd of “elephants” on the road. I have been looking at the auctions for another one.
3 liters in THIS Geo would be a scream!..........
I can believe that....
I always thought the Suzuki jeepy-looking cars were nice. I got that kind of mileage with the Highlander Hybrid and it was bigger and just as easy to park. I get only about 20 in the Envoy but I feel much safer in it.
I wish it didn’t make me feel so aggressive though. I admit I’ll probably work up to a Hummer and then I’ll be addicted...
Oh, wait, he made a Froufer! He meant 44 miles/gallon!
I never was able to get the Metro or the Precis to go fast enough to enter the freeway. And the screaming engine was too much for me.
I would never want to again drive one in conjested freeway traffic, but on the less conjested Interstate highways they are not so bad. You never want a big rig coming up behind you on a hill. The rig doesn’t want to slow down losing momentum, and the little car can’t accelerate to get out of the bastard’s way.
Exactly the same reason why big rigs don’t want little riceburners slipping in front of them too quickly.
I most admit the air conditioner was too small, fortunately I worked the night shift so it wasn’t that big of a deal for me. As far as having one in Texas, that probably won’t work out to good.
Here's a "riceburner" that the truckers only see the taillights of.........receding in the distance.....
Reminds me of the 83 diesel rabbit my boss had once. Had to turn off the AC whenever you wanted to pass. Which took a LONG time.
My Chevy 2500 HD 4x4 Duramax Diesel gets 17/18 mpg @ 79mph with the cruise control set.
Great! Do you pull a trailer or camper or boat from time to time?..........
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