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Delphi, a major parts supplier to automakers, is developing an engine technology that could improve the fuel economy of gas-powered cars by 50 percent, potentially rivaling the performance of hybrid vehicles while costing less. A test engine based on the technology is similar in some ways to a highly efficient diesel engine, but runs on gasoline...

The Delphi technology is the latest attempt by researchers to combine the best qualities of diesel and gasoline engines. Diesel engines are 40 to 45 percent efficient in using the energy in fuel to propel a vehicle, compared to roughly 30 percent efficiency for gasoline engines. But diesel engines are dirty and require expensive exhaust-treatment technology to meet emissions regulations.

For decades, researchers have attempted to run diesel-like engines on gasoline to achieve high efficiency with low emissions. Such engines might be cheaper than hybrid technology, since they don't require a large battery and electric motor.

In conventional gasoline-powered engines, a spark ignites a mixture of fuel and air. Diesel engines don't use a spark. Instead, they compress air until it's so hot that fuel injected into the combustion chamber soon ignites. Several researchers have attempted to use compression ignition with gasoline, but it's proved challenging to control such engines, especially under the wide range of loads put on them as a car idles, accelerates, and cruises at various speeds.

Delphi's approach, which is called gasoline-direct-injection compression ignition, aims to overcome the problem by combining a collection of engine-operating strategies that make use of advanced fuel injection and air intake and exhaust controls, many of which are available on advanced engines today.

For example, the researchers found that if they injected the gasoline in three precisely timed bursts, they could avoid the too-rapid combustion that's made some previous experimental engines too noisy. At the same time, they could burn the fuel faster than in conventional gasoline engines, which is necessary for getting the most out of the fuel.

http://www.technologyreview.com/energy/ ... 2012-05-17

They've had this shit for decades. The oil industry and the carmakers agreed to keep the profits rolling in. Now that many carmakers are kind of fucked, you'll see some of this 40 year old fuel efficiency shit start coming out as 'new' technology.

Shafpocalypse Now wrote:They've had this shit for decades.

They haven't had the computer controls coupled with the sensors and the computer controlled fuel injectors and valves, etc to execute these engines for decades. The key to the Delphi engine is that it constantly senses and adapts.

The big bad corporations have largely been responding to what consumers wanted. Gas has been cheap and it's still too inexpensive if you count costs of smog, congestion and wear on roads. All of the electric cars and other "green" initiatives in the world will do less to encourage more efficient vehicles and "energy independence" than a simple gasoline tax could.

Shafpocalypse Now wrote:They've had this shit for decades. The oil industry and the carmakers agreed to keep the profits rolling in. Now that many carmakers are kind of fucked, you'll see some of this 40 year old fuel efficiency shit start coming out as 'new' technology.

Chris Rock: The government curing AIDS? That's like Cadillac making a car that last for fifty years... and you know they can do it! But they ain't gonna do something that fucking dumb! Shit! They got metal on the space shuttle that can go around the moon and withstand temperatures up to 20,000 degrees. You mean to tell me you don't think they can make an El Dorado where the fucking bumper don't fall off?

nafod wrote:

Shafpocalypse Now wrote:They've had this shit for decades.

They haven't had the computer controls coupled with the sensors and the computer controlled fuel injectors and valves, etc to execute these engines for decades. The key to the Delphi engine is that it constantly senses and adapts.

Honda was doing this with a two stroked based FI engine in the 80's. Doesn't take very sophisticated system to get better economy, takes a really really sophisticated system to manage emissions in both 2stroke and diesel engines.

Not enough details on the actual motor to get a sense of anything new..But I'm all for anyone repackaging the two cycle...I think all this hanky panky with valves is silly when there is a superior design that gets even better with engine management.

They had modified Chevy 350s back in 1971 getting 28-32 MPG running about 270 HP. A 454/455 could be modified to get 23-26. I've SEEN one of the 350s, though take that with a grain of salt, because it wasn't running, it had a highly modified and unusual carburetor and air delivery system on top of it.

Growing up in a GM town (and knowing more than a few GM researchers) lets you hear lots of interesting stories.

Chris Rock's story? Metallurgists came up with an alloy for bodies that rusted out 4x quicker than sheet metal. You can see the distinctive pattern in many early-mid 70s GM vehicles...it was so popular that they sold it extensively to the Mopar brands, not sure about Ford.

So, you'd think that with the modern computer controlled cars you'd get stellar mileage, but you don't....same old story, same old collusion with big oil.

Shaf, as usual, is correct.

Watch Race to Save the Planet. Volvo had a prototype car that got 80 mpg on a mixed fuel in 1977 IIRC. That would be before computer controlled engines.

Able to produce, and willing to produce are very different things when $$$ is involved.

Pinky wrote:The big bad corporations have largely been responding to what consumers wanted. Gas has been cheap and it's still too inexpensive if you count costs of smog, congestion and wear on roads. All of the electric cars and other "green" initiatives in the world will do less to encourage more efficient vehicles and "energy independence" than a simple gasoline tax could.

The reason we haven't seen this technology exit R&D and hit the production line is quite simple. The tolerance for a diesel engine are extremely tight, making diesel engines more expensive to produce. Now introduce gasoline as the fuel source in a diesel engine and your problems start to really escalate. Gasoline has a lot more energy than diesel, and is much more explosive. Meaning your tolerances in machining has to be even tighter and (like nafod stated) you need a whole lot sensors and computing power to control the process so as not to destroy the engine.

Batboy2/75 wrote: (like nafod stated)

fuckin' A, bubba

Shafpocalypse Now wrote: So, you'd think that with the modern computer controlled cars you'd get stellar mileage, but you don't....same old story, same old collusion with big oil.

We could have much better mileage than we do, it's true, but I think it's mostly because they put most of the extra efficiency of modern engines into getting more horsepower. If you look at the trends over the decades, the mpg has edged up over time, but the horsepower in our ordinary cars has just skyrocketed by comparison. I think the emphasis on horsepower is strongly consumer-driven. People complain when a vehicle has less power than it's competitor's equivalent, at least Americans sure do.

Here's a pic I ripped off a "treehugger" site.

The Honda Accord, which sold well in the US, over a 25 year span:

For comparison, the Ford Escort base package went from 68 hp in 1981 to 130 hp by 1999.

It's not the increase in horsepower that is the problem, it's the increase in weight. The horse power increase was needed to haul the extra weight around. Your accord in the graph above gained nearly 1/2 ton in weight, it's amazing it gets the mileage it does, which is pretty favorable to the earlier accord.

If you were to put a really small engine of today into a honda civic of the late 80's - it would get incredible mileage.

In college, a guy I knew used to drive a car on the highway for the "wide load" trucks. He got paid by the mile. He had an early model Dodge neon, and he took out the back seat, passenger seat, and some other stuff to make it lighter and he got mileage in the 40's (of course they weren't going too fast either)

Escort only went up a couple hundred pounds. It's true the cars got bigger generally. Sales shifted to bigger types as well, like SUVs. That part is totally consumer driven.

Schlegel wrote:

Shafpocalypse Now wrote: So, you'd think that with the modern computer controlled cars you'd get stellar mileage, but you don't....same old story, same old collusion with big oil.

We could have much better mileage than we do, it's true, but I think it's mostly because they put most of the extra efficiency of modern engines into getting more horsepower. If you look at the trends over the decades, the mpg has edged up over time, but the horsepower in our ordinary cars has just skyrocketed by comparison. I think the emphasis on horsepower is strongly consumer-driven. People complain when a vehicle has less power than it's competitor's equivalent, at least Americans sure do.

Here's a pic I ripped off a "treehugger" site.

The Honda Accord, which sold well in the US, over a 25 year span:

Cool graphic. Not sure but I think the environmental requirements hurt the gas mileage. I used to drive an old Civic with a cracked head. Still ran fine, just no power up hills. Car was ugly as hell, but I miss it.

Schlegel wrote:Escort only went up a couple hundred pounds. It's true the cars got bigger generally. Sales shifted to bigger types as well, like SUVs. That part is totally consumer driven.

Horsepower increased because more advanced technologies became more common, and economy cars like the escort were at the bottom of the food chain back then and got technology as it trickled down.

The extra horsepower is a moot point, unless you're flooring the gas pedal on the car all the time. Just because the max horsepower increased doesn't mean you are using that extra power all the time.

Weight is the mileage buster, not high horsepower engines.

When accelerating, you need to overcome mass. The more mass, the more force (horsepower and indirectly gasoline) you need to overcome it. Through newer technologies such as direct injection and variable valve timing engineers are able to extract more horsepower for about the same amount of fuel (a better and more controlled flame front)

At steady state (on the highway), you only need to produce enough power to overcome internal friction (compression, bearings, drivetrain...) wind resistance and rolling resistance. Depending on the vehicle, it only takes 15-20hp, so whether your engine is capable of producing 100 or 400 hp at that point it doesn't matter a whole lot. (which is why Ford can make a Mustang that gets 30mpg highway and yet has 50% more HP than the V8 5.0 had in the mid 80's)

Weight is one of the huge problems with electric cars. You want to increase distance the car can travel, you need to increase the battery storage capacity - which increases the weight. Increase the weight too much, then you need to upgrade the electric motors and the cycle repeats.

If there were a way to have cars get electricity like subways or the high speed trains in Europe, we could make electric cars that are fairly efficient.

What's interesting is the often poopoo'd system GM has. Take the new 2013 Malibu Eco
http://www.chevrolet.com/malibu-eco-fue ... n/?seo=goo
This vehicle is rated at 38 highway, and the outgoing 2012 Malibu without the "E assist" was rated at 33 MPG highway.

It has a small "E Assist" 15 hp motor, requiring only a fairly small battery (compared to the volt or prius) to maintain it.
The electric motor can kick in to assist the engine. For example, when on the highway, you are going on a slight incline for a few seconds, if you can use electric to assist with the extra power needed right then, rather than gas, you can save gas. Then, when you are on a slight decline, or you brake, the battery recaptures some of the energy.

If we want really efficient cars, besides the latest in engine technologies, we need to make cars lighter. Weight went up for a variety of reasons, quality being one (they are much stiffer today than even a decade ago) and safety. Safety items increased weight (10 airbags, govt mandated side impact protection bars, etc.) - cars are much much safer in crashes today than a decade ago, but that safety came at the cost of weight.

One culprit to weight, is rotational mass. Those 22" rims the bruddas put on their SUV's actually hurt mileage a lot, to the tune of around 2 mpg.