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A New Lease On Internal Combustion

kdawson posted more than 7 years ago | from the more-power-to-ya dept.

Hardware Hacking 431

Somnus suggests we check out the latest issue of MIT's Technology Review, where researchers describe how they can dramatically boost engine output and efficiency by preventing pre-ignition, or "knock." How they do it: "Both turbocharging and direct injection are preexisting technologies, and neither looks particularly impressive... by combining them, and augmenting them with a novel way to use a small amount of ethanol, Cohn and his colleagues have created a design that they believe could triple the power of a test engine."

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What new technology? (0, Troll)

Reason58 (775044) | more than 7 years ago | (#18338955)

How long before this is bought/patented by oil companies and sealed away in the same warehouse as the Ark of the Covenant.

Hard to hide now (1, Informative)

Engineer-Poet (795260) | more than 7 years ago | (#18339105)

Once you've filed a patent (one synonym of "patent" is "obvious") and received as much news play as this has, it can't be hidden.

Any attempt to hide it will get as much bad press as Chevron's blocking of high-capacity NiMH batteries for EV's through their Cobasys venture. It will invite things like compulsory licensing.

Re:Hard to hide now (2, Informative)

Rei (128717) | more than 7 years ago | (#18339509)

Huh? You mean this Cobasys [] ?

"Cobasys, the First Name in Nickel Metal Hydride Battery Solutions, provides commercial NiMH battery systems for the hybrid electric vehicle (HEV), electric vehicle (EV) and 42 Volt transportation markets. The NiMHax brand for EV, HEV, HD HEV, and 42 Volt systems, provides flexible standardized architecture for a wide-range of vehicle solutions."

Doesn't look very blocked to me. Let's search for more info. The company is greatly expanding... asp []

"ORION, MI, May 18, 2005 -- Cobasys, a leader in advanced Nickel Metal Hydride (NiMH) battery technology, today announced the grand opening of its new 84,000 square-foot headquarters in Orion, Michigan. The engineering, development, administrative, sales and marketing facility currently houses 175 of the company's 220 employees, and is expanding to accommodate anticipated employment growth of an additional 25 percent through 2006."

Further searches reveal that all sorts of cars are using Cobasys batteries -- for example, the Saturn Vue. Two companies also produce batteries on license from them -- Panasonic and Sanyo, which produce other hybrid car batteries. It looks like the negative press Cobasys has earned is because it aggressively enforces its patents against NiMH interlopers (one of which happened to produce the EV1's batteries). Looks, by all means, like they want to be the only ones selling NiMH in the US, and selling them in bulk -- not that they don't want anyone selling them.

From what I've seen, I have to agree with's automotive blog [] :

"Chevron should be lauded for investing in technology that reduces the demand for its main products (gasoline). The company realizes that hybrids are a great opportunity, so following the "if you can't beat 'em, join 'em), they are profiting from the growth of hybrids."

Oil companies will either adapt (by becoming "energy" companies) or die as the world slowly changes energy sources. That doesn't seem to stop the "it's a conspiracy to suppress energy-saving technology!" nuts.

Re:What new technology? (1)

couchslug (175151) | more than 7 years ago | (#18339129)

It's an MIT research product.
Anyone with knowledge of how they handle IP produced by their researchers care to comment?

brief review of article (4, Informative)

Xiph (723935) | more than 7 years ago | (#18339189)

Yes, i'm whoring on the firstpost reply... Daniel Cohn from MIT claims to have increased the efficiency of a regular car engine, by altering the fuel injection system to combine direct injection, turbo charging and alchool into one system.

A vehicle that used this approach would operate around 25 percent more efficiently than a vehicle with a conventional engine.
They state that it is key to overcome the knock effect, from when the gas explodes before it's supposed to be ignited by the sparkplug. This is done by using the cooling effect of evaporating alcohol. They also recognize the fact that these addons makes the engine more expensive, but claim that it will be offset by not needing as large an engine. (It does not appear as if it has been properly analyzed). They claim that because it's a hybrid of existing technologies it could be ready as soon as 2011.

This should be a lot more accurate than the original summary.

Re:brief review of article (1, Troll)

dgatwood (11270) | more than 7 years ago | (#18339867)

It's a cool idea, but it's about twenty years too late to do any good, IMHO. The modified engine requires two separate tanks, one for gasoline, one for pure ethanol (or possibly just a high ethanol mixture like E85). This means that gas stations would have to be retooled to provide ethanol. If you're going to retool the gas stations to provide ethanol, you might as well retool them to provide hydrogen instead. The whole reason for sticking with gasoline is that the distribution mechanism is already in place. Once you take that away and have to start changing things, that benefit evaporates faster than the ethanol....

And don't get me started about the customer confusion this would cause. "You mean my engine will stop running if I don't keep both tanks full?" If you think printers are bad, imagine your SUV suddenly having the engine capacity of a Yugo because you ran out of ethanol (if the engine runs at all). And I don't think they've considered the safety issues, either. Pump the wrong fuel into the wrong tank, and bad things could happen. That means that the new nozzles would have to be incompatible with gasoline nozzles and vice-versa or grandma's going up like a rocket ship.

It's a neat idea in theory, and perhaps it will find an appropriate application, but I don't think cars are the right application for the technology. IMHO, by 2011, gasoline-powered vehicles should no longer even be manufactured. Even at maximum efficiency, they are only about 20% efficient. If it's 25% more efficient, that's only 25% efficiency, and that isn't counting loss from the transmission, etc.. Using a gasoline reformer, fuel cell, and electric motor, as best I can tell from running the efficiency numbers for various key parts of the system, we should already be able to beat those numbers by a significant margin (say a factor of two), and that's with technology that is available now and doesn't require any special fuel source....

Re:What new technology? (4, Funny)

Rei (128717) | more than 7 years ago | (#18339277)

It might be a while. They're still busy relocating Jimmy Hoffa's body, plotting out new wars in the Middle East, and assassinating more people connected to the moon landing hoax.

Re:What new technology? (2, Funny)

AK Marc (707885) | more than 7 years ago | (#18339813)

Are you implying that they haven't done things like, say, help innovate Lithium-based batteries, then prevent their use in electric cars?

Re:What new technology? (0)

Anonymous Coward | more than 7 years ago | (#18339417)

That would be Warehouse 23 [] , right?

Check out the 07 MINI - it has this stuff already. (4, Informative)

sbaker (47485) | more than 7 years ago | (#18339433)

The '07 MINI Cooper'S has a 4 cylinder 1.6 liter direct-injected twin-turbocharged engine - and since most fuel in the US now contains 10% ethanol, I'd say the "experimental" technology these guys are pushing is already out there in at least one production car. The problem with knocking has been nailed a bazillion years ago - just about all modern cars have an anti-knock sensor that can richen the mixture if it detects signs of knocking - but with high octane gasoline - it only very rarely has to actually do that - so the "problem" of knocking isn't really there. The only time the MINI actually does something like that is when the dumb user filled the thing with regular low-octane gas instead of 'the good stuff'.

Add to that that the MINI has goodies like electric oil, power steering and water pumps that can actually be turned off (rather than merely bypassed) when not needed - so the engine reaches it's most efficient temperature faster and you aren't burning fuel circulating fluids that don't need to be circulated yet. It has computer controlled inlet and exhaust valves - so the timing is infinitely variable - and can be varied separately for each cylinder. For short bursts of accelleration, the car has an 'overboost' feature from the turbo - which won't help you much for prolonged hard accelleration - but is great for a rapid burst of speed for overtaking, blasting out of a corner (FUN!) or blowing away those bloody ugly Scion xB's at traffic lights (a personal mission of mine, I might add).

Re:Check out the 07 MINI - it has this stuff alrea (4, Insightful)

GameMaster (148118) | more than 7 years ago | (#18339645)

You either need to read the article or, if you have, brush up on your reading comprehension skills. The technique used in the article is supposed to allow them to push the turbo pressure much higher than any modern car can handle, even when using high octane fuel. They're talking about using a separate direct injection system to pump a small amount of pure ethanol into the cylinder out of phase with the gasoline. It would cool the cylinder enough to stop knock when the gas is injected at extreme pressures. Supposedly, you would have to replace the ethanol about as often as you have to replace the oil (every few months).

Next time, please try reading the article instead of seeing "ethanol" and "turbocharger" in the summary and shooting your mouth off.


Re:Check out the 07 MINI - it has this stuff alrea (3, Informative)

hardburn (141468) | more than 7 years ago | (#18339875)

The '07 MINI Cooper'S has a 4 cylinder 1.6 liter direct-injected twin-turbocharged engine - and since most fuel in the US now contains 10% ethanol, I'd say the "experimental" technology these guys are pushing is already out there in at least one production car

As the article notes, direct injection has been around for a while (since the '50s). Turbochargers are older than that. The idea here uses direct injection in a novel way.

. . . just about all modern cars have an anti-knock sensor that can richen the mixture if it detects signs of knocking - but with high octane gasoline - it only very rarely has to actually do that - so the "problem" of knocking isn't really there.

The problem isn't stopping current engines from knocking. The problem is to increase compression ratios or boost of an engine without introducing knocking. Increasing the amount of gas in the mixture only makes your fuel efficiency worse.

The key to this new idea is that the ethanol is injected separately from the regular gas (specifically, during the compression phase). Naturally, you'll need a separate tank of ethanol, which the article claims would need to be replenished about as often as a oil change.

As we know from thermodynamics, matter going through a phase change from liquid to vapor will suck away a lot energy. Ethanol has the nice quality that it will go through a phase change at a lower temperature compared to water.

Thermodynamics also tells us that as pressure increases, so does temperature. In a normal engine, the piston will compress the fuel/air mixture, thus increasing the temperature of the mixture. If the temperature gets too high, the mixture will ignite on its own. This is more likely if your engine has too high of a compression ratio or you're using some kind of boost system (turbo or superchargers). This is why cars with turbos often have intercoolers.

What they're doing here is increasing the compression ratio and/or adding a turbo. You can choose to slap on an intercooler if you wish. As the piston goes through the compression stroke, the fuel/air mixture gets hotter as before, but then some ethanol is injected, which vaporizes, thus cooling the mixture. The mixture is then ignited by a spark plug normally. Brilliant.

Re:What new technology? (1)

dbschman (548553) | more than 7 years ago | (#18339837)

Another company has patented another method of increasing the efficiency of a turbocharger without the need of injecting ethanol: []

Re:What new technology? (0)

Anonymous Coward | more than 7 years ago | (#18339855)

How long before this is bought/patented by oil companies and sealed away in the same warehouse as the Ark of the Covenant.

It won't. The oil companies have the consumer on a subscription model. As long as the average consumer continues to pay their $150/mo subscription, they actually prefer that the consumer use less gas in doing so. That may be part of the reason that this article had a "vs hybrid" spin. Hybrids are a staggeringly effective model (potentially better power, efficiency, handling, features and mileage) but they have the "flaw" of being able to be adapted to use any source of electricity.

I find many of life's problems... (4, Funny)

26199 (577806) | more than 7 years ago | (#18338957)

...become simpler with the addition of a small amount of ethanol.

In a large glass.

Re:I find many of life's problems... (1)

Goldenhawk (242867) | more than 7 years ago | (#18339099)

"Ethanol would be stored in its own tank or compartment and would be introduced by a separate direct-injection system."

This does tend to give new meaning to the term "fuel siphoning". Imagine the fun...


Re:I find many of life's problems... (1)

Penguinshit (591885) | more than 7 years ago | (#18339145)

imagine the brain damage....

Re:I find many of life's problems... (1)

LunaticTippy (872397) | more than 7 years ago | (#18339741)

Mankind has made it to the Moon with thousands of years of ethanol-induced brain damage.

You might be thinking of methanol, that is only fun once or twice.

What would you say... (2, Funny)

Skadet (528657) | more than 7 years ago | (#18339323)

What would you say to some nice ethanol?

I'd say, "Don't get too comfortable in that glass!"

Old (2, Interesting)

jevring (618916) | more than 7 years ago | (#18338961)

Wow, this is yesterdays news. People in the tuning industry have been controlling "knock" in various ways for a long time. Either by raising the octane number on your ful (add ethanol or booster), so that you can had move advanced ignition timing, or simply retarding your timing and using the same octane rating fuel as you normally use

Re:Old (3, Insightful)

AP2k (991160) | more than 7 years ago | (#18339101)

Even still, water and alcohol injection used to cool the charge is not new, and has been around since the 30's.

Whoever wrote the article doesnt understand why SUVs and trucks have big engines. Its not because they are powerful, its because they need lots of torque. You can pull a trailor up a hill in an S2000 just like you can a road tractor, but the tractor will use much less fuel and less wearing of the engine doing it.B enignes arent going anywhere in SUVs any time soon, despite this seemingly "revolutionary" new technology.

I predict this will end up as a failure just like the last time an engine manufacturer tried this: Turbo_Jetfire []

No matter how novel the technology, when the product's life depends solely on the customer, your product wont usually stay on the shelves for very long.

Re:Old (5, Informative)

iamhassi (659463) | more than 7 years ago | (#18339251)

"People in the tuning industry have been controlling "knock" in various ways for a long time."

Exactly. This sounds a lot like water injection, which has been around forever and does increase mpg by about 10% in turbo cars and allows lower octane fuel.

Here's what's going to kill the technology from TFA:
"Ethanol would be stored in its own tank or compartment and would be introduced by a separate direct-injection system. The ethanol would have to be replenished only once every few months, roughly as often as the oil is changed. A vehicle that used this approach would operate around 25 percent more efficiently than a vehicle with a conventional engine."

This is exactly like water-injection [] and it's why we don't see water-injection in vehicles. No one wants to have a separate tank that we need to remember to fill-up, and the 10% increase provided by water just isn't enough. This is the same story except it's ethanol, not as easy to find as water, and it's 25% better mpg instead of 10%.

We will never see a production ethanol injection vehicle. Vaporware with a capital V

Re:Old (4, Insightful)

drinkypoo (153816) | more than 7 years ago | (#18339393)

This is exactly like water-injection and it's why we don't see water-injection in vehicles. No one wants to have a separate tank that we need to remember to fill-up, and the 10% increase provided by water just isn't enough. This is the same story except it's ethanol, not as easy to find as water, and it's 25% better mpg instead of 10%.

But the story is different because the system will know what to do when it runs out of ethanol, which is to say retard timing and reduce mileage and power output until you add more ethanol. Water injection is aftermarket and usually not compensated for automatically.

The mileage improvement is pretty compelling and I think we'll see it implemented if fuel prices rise much more.

Re:Old (-1)

Anonymous Coward | more than 7 years ago | (#18339585)

The mileage improvement is pretty compelling and I think we'll see it implemented if fuel prices rise much more.

That's assuming the U.S. ramps up domestic ethanol production. Right now, Brazil is the center of the ethanol universe, and the U.S. isn't going to embrace a technology that ties us to Chavez.

Re:Old (1)

YU Nicks NE Way (129084) | more than 7 years ago | (#18339647)

Hector Chavez is President of Venezuela. He's got nothing to do with ethanol production; in fact, the only reason we care about him is the oil reserves his country sits on, and sells to us.

Re:Old (1)

GameMaster (148118) | more than 7 years ago | (#18339889)

Actually, his name is Hugo but, otherwise, you are correct. While the president of Brazil is pretty left leaning (and somewhat of a friend of Chavez's) the US government would much prefer dealing with him over Chavez.


No, the story is exactly the same (1)

GameMaster (148118) | more than 7 years ago | (#18339863)

This link was posted by someone else responding to the original post. Turbo_Jetfire []

If you read the section, you'll notice that, even without fancy computer controls, they had designed the engine to retard timing when the reservoir was empty. The reason they discontinued the engine really was that people just didn't bother keeping the thing filled.

Unfortunately, people are lazy. Unless the system is designed to kill the engine when the ethanol tank runs dry they won't bother keeping it full. If you did kill the engine that way they would, simply, refuse to buy the car (as was the case in the 60's).


Re:Old (5, Informative)

MightyYar (622222) | more than 7 years ago | (#18339261)

From TFA (and this goes for the reply above mine as well as the parent):
"Similar approaches, some of which used water to cool the cylinder, had been tried before. But the combination of direct injection and ethanol, Cohn says, had much more dramatic results."

Show me someone in the tuning industry using directly injected ethanol along with a turbocharger and regular gas. I've never heard of this approach.

Re:Old (1)

mvdwege (243851) | more than 7 years ago | (#18339495)

Try the BMW801 aircraft engine, as used by the Luftwaffe in WWII in the Focke Wulf FW190. That had fuel injection, supercharger and the MW50 ethanol injection system.


Re:Old (2, Informative)

MightyYar (622222) | more than 7 years ago | (#18339673)

That's great, but the MIT spin-off is using DIRECT INJECTION, not fuel injection. There is an injector that actually squirts ethanol directly into the cylinder, not into the intake. Much higher pressures. Except for a German sports car back in the 50's, no one put direct injection into an automobile until the late 90s. While it is true that this is just an updated version of an old idea, it's still interesting enough to be called news if they can achieve hybrid-like fuel savings with just an internal combustion engine.

Re:Old (1)

StikyPad (445176) | more than 7 years ago | (#18339907)

Regardless, dual fuel will be the catch. Aside from convenience issues of filling up two tanks, E85 isn't even available everywhere in the US, and it's practically nonexistant outside of the US, Brazil, and Sweden. That means you can't take road trips, but more importantly it means the market is probably too small to be worth the effort.

Re:Old (5, Informative)

dr_wheel (671305) | more than 7 years ago | (#18339313)

I was thinking the same thing when I started reading the article. A quick search at any of the major car enthusiast websites will lead you to dozens of threads on direct injection and forced induction (turbocharging). This isn't news. There are already direct injection, turboed factory motors out there. The 2007 Saturn Sky Red Line, for example, is powered by a 2.0-liter direct injection turbo engine. You may have heard of another auto manufacturer using this same technology in it's diesel engines... VW's TDI (Turbo Direct Injection).

The "new" part comes where they are using ethanol direct injection. It's a new twist on an old idea. See also water-methanol injection: nes) []

Sure, it's not anything evolutionary. And the article might read like 1st Grade literature for anyone who is familiar with cars and tuning... but it's still interesting stuff.

Re:Old (2, Informative)

Loualbano2 (98133) | more than 7 years ago | (#18339613)

This actually is somewhat new.

What they are doing is different from old alcohol injection that merely mixed the injected fuel with ethanol before it went past the intake valve.

This method is using directly injecting ethanol similar to a diesel motor. The advantage seems to be the same effect but with way less ethanol. The article quoted having the ethanol refilled on the order of months.

While the effects of alcohol injection are well known and are not new, this method seems to make it way more practical, which is new.

slashdot (-1, Flamebait)

Anonymous Coward | more than 7 years ago | (#18338963)

fuck all you know-nothing cunts.


The Grinch that stole the commons. (-1, Flamebait)

Anonymous Coward | more than 7 years ago | (#18338973)

"How they do it: "Both turbocharging and direct injection are preexisting technologies, and neither looks particularly impressive... by combining them, and augmenting them with a novel way to use a small amount of ethanol, Cohn and his colleagues have created a design that they believe could triple the power of a test engine.""

And remember folks, patents are evil. So cross your fingers and hope.

Rudolph Diesel (5, Insightful)

LiENUS (207736) | more than 7 years ago | (#18339027)

Congratulations You've discovered the same thing as Rudolph Diesel except that you don't quite have it right. You don't need to use ethanol or port injection ditch both of those and use good ol fashioned vegetable oil. 0 preignition and you can turn the boost way up on a tiny engine.

Why funny? (1)

Skadet (528657) | more than 7 years ago | (#18339399)

Why is this rated "funny"? Mythbusters did this:

"Although there's no word on damage to the engine from using used cooking oil, a diesel-fueled car did run on it. However, the MythBusters speculate that once this alternative fuel achieves a significant interest level among the public, used cooking oil will be hoarded as a saleable commodity. The used cooking oil also did not quite fit the requirement of improved fuel efficiency, as it yielded approximately 10% less distance for an equivalent amount of diesel."

See here [] and here (scroll down) []

Re:Why funny? (3, Informative)

LiENUS (207736) | more than 7 years ago | (#18339513)

the beauty of a diesel is it runs on any oil, used cooking oil, cod liver oil, diesel fuel oil, motor oil. Properly setup itl'l run on used motor oil, used transmission fluid, used any oil.

Re:Rudolph Diesel (2, Insightful)

JesseL (107722) | more than 7 years ago | (#18339823)

0 preignition and you can turn the boost way up on a tiny engine.
It's actually more like 100% preignition in a diesel, but they're built to withstand it without grenading.

Internal Combusiton? (2, Funny)

Reverend528 (585549) | more than 7 years ago | (#18339033)

This headline made my brain spontaneously combusit.

Re:Internal Combusiton? (1)

atrocious cowpat (850512) | more than 7 years ago | (#18339565)

This headline made my brain spontaneously combusit.
It's spelled "healdine", you insensitive cold!

What? (0)

Anonymous Coward | more than 7 years ago | (#18339037)

"Both turbocharging and direct injection are preexisting technologies, and neither looks particularly impressive... by combining them, and augmenting them with a novel way to use a small amount of ethanol, Cohn and his colleagues have created a design that they believe could triple the power of a test engine."

Have those two NOT been previously combined before, or what?

In any case, triple the power sounds awesome. If real, I want that tech in my motorcycle. As a two stroke.

Re:What? (1)

$RANDOMLUSER (804576) | more than 7 years ago | (#18339107)

Mercedes Benz had direct injection on their race cars like back in the mid 50s or so. The problem was you needed about 600 PSI (IIRC) to make it work. If they're increasing the compression ratio, then they're going to need even more.

Re:What? (1)

confused one (671304) | more than 7 years ago | (#18339703)

This is really a non-problem that was worked out in production direct-injection cars over a decades ago. Many modern diesels use electronic direct injection, which, in a modern diesel (>20:1 compression), requires pressures significantly higher.

Re:What? (1)

cyclopropene (777291) | more than 7 years ago | (#18339555)

Have those two NOT been previously combined before, or what?

Yes, they have. Especially in diesels (all those Volkswagen TDI's you see around, it stands for Turbo Direct Injection [] ). The standard engine in an Audi A4 (as well as the Volkswagen Passat among others) is now the 2.0T FSI [] turbo direct injection gasoline engine.

Pretty soon, you'll have a turbo Diesel (1)

johnny cashed (590023) | more than 7 years ago | (#18339045)

Just with a spark plug instead. This is similar to water injection and water/methanol injection on a turbo gasoline engine.

Re:Pretty soon, you'll have a turbo Diesel (2, Informative)

drinkypoo (153816) | more than 7 years ago | (#18339281)

You can already do alcohol/nitrous injection into a diesel engine for power, and water injection has been fairly common for diesel performance for quite some time now. But because diesels don't have knock (they OPERATE by compression/hotspot ignition) this technology is utterly inapplicable there.

Not the final solution (3, Insightful)

dal20402 (895630) | more than 7 years ago | (#18339049)

I suppose my first question is, when the owner inevitably lets the ethanol run out, what happens? Can the engine computer dial down the boost enough to prevent detonation? Or does the engine just have to shut down?

That aside, it's always great to improve internal-combustion efficiency, but the real solutions will have a more dramatic effect than this. My own view is that the solution should be a plug-in series hybrid with about 60 miles of electric-only range and the ability to run maybe 400 more with the engine providing generator power. This would not seriously compromise the essential attributes of modern cars, while *dramatically* (think 80% or more) improving their fuel economy in many real-world usage patterns.

Then we should have nuclear power behind all those 220v outlets... and 90% of cars should be much smaller, with people able to obtain bigger trucks for big jobs on demand from time-share or rental companies... a guy can dream, can't he...

Re:Not the final solution (1)

gurps_npc (621217) | more than 7 years ago | (#18339181)

When the Ethano runs out, the engine begins to "knock". It ignites before the right time. This decreases fuel efficiancy quite a bit, and could theoretically damage the engine if you did it long enough.

But as you pointed out, a smart engine should be able to recognize that Knock is occuring. While the computer can not change the size of the cylinders, it could change the amount of fuel/air injected. This would reduce the chance of damage, but severly impair engine performance.

The rest of your ideas are good, but will take quite some time. Nuclear power still needs both some more advancements and some better press before we begin to truly accept it. (And Russia should shoot anyone that suggets "Our plant is so good we don't need the essential safety feature X" - which is what they said when they decided not to put a containment roof over Chernobyl.)

Nowhere near final, but FAR better than E85 (1)

Engineer-Poet (795260) | more than 7 years ago | (#18339239)

I suppose my first question is, when the owner inevitably lets the ethanol run out, what happens?
The engine will not be able to run at high boost (power).

Can the engine computer dial down the boost enough to prevent detonation? Or does the engine just have to shut down?
That depends on the static compression ratio of the engine, but if it's kept down to a reasonable value the engine should be able to run but the controller will open the turbo wastegate. If the static compression ratio is high enough to knock at close to atmospheric pressure in the manifold, the controller would have to restrict the throttle opening.

This scheme is a stopgap, pure and simple. 30% is nowhere near good enough — we need plug-in hybrids to displace 80% of our liquid fuel (for starters), not 30%. But when you compare the efficiency losses of gasohol and E85 to the efficiency gains of the smaller turbo engine, and consider that this engine has the potential to run on 100% ethanol (complete flex-fuel operation) and on ethanol with some admixture of water (reducing the energy required for distillation and allowing the ethanol to be shipped by pipeline where it might pick up water), this is a huge improvement.

Unfortunately, it won't be good for much if we have to trade off food against motor fuel.

Re:Not the final solution (1)

codepunk (167897) | more than 7 years ago | (#18339259)

Yes it is called a knock sensor and they have been in use for years. In most cases the knock lets the computer know it is happening and it will then retard the timing to eliminate the knock. In this case the computer only has to retard the timing and adjust the waste gate to drop the boost pressure to eliminate the knock.

Re:Not the final solution (1)

Xiph (723935) | more than 7 years ago | (#18339263)

if you'd bother reading TFA you'd realized they did answer that question. You'll need to add more alcohol about as often as you change oil, the lack of oxygen to peoples brains is a much bigger problem

Re:Not the final solution (1)

dal20402 (895630) | more than 7 years ago | (#18339395)

If you'd bother reading my comment, you'd see I was asking about neglectful owners, not anything in TFA. How many of the people you know actually change their oil on time?

If these were in large-scale use the ethanol *would* run out. Often. My question was whether, when that happens, you get reduced power or your car stops running.

Re:Not the final solution (1)

ZDRuX (1010435) | more than 7 years ago | (#18339353)

I suppose my first question is, when the owner inevitably lets the ethanol run out, what happens? Can the engine computer dial down the boost enough to prevent detonation? Or does the engine just have to shut down?

Most if not all of today's forced induction (and some naturaly aspirated) cars have knock sensors which will automatically retard the ignition timing when knock shows up, either from too much heat, bad air/fuel mixture, too much combustion chamber pressure, etc.. So yes, you could run out of any sort of "additive" and still have somewhat of an assurance that your engine won't blow up on the way to the store.

As for the actual post, this is nothing new. This has been used by people "in the know" all the time to increase the ammount of power an engine produces without melting away your pistons by using something called Toluene, which is now a banned substance in the U.S. and Canada, but can still be purchased at some paint supply stores because it's a paint thinner, but apparently has been used to make Meth, or some other type of drug.

For those interested - "knock" is when the fuel mixture inside your combustion chamber ignites before the piston actually makes it all the way to top, which as you can imagine is *really* bad. You are in fact, trying to compress an explosion while it is igniting, which creates incredibly hot temperatures inside the chamber causing all sorts of nasty stuff. If this last long enough (over the course of months or years if its small enough) it will eventually start chewing away at your piston rings, causing "blow by" which robs your engine of power, makes your oil get into the combustion chamber, smoke starts coming out your tail pipe, and things just go downl hill from there.

If you wish to make your own "race gas" or want to know how this stuff works and how it has been used for tens of years, visit this FAQ []

Re:Not the final solution (1)

drgonzo59 (747139) | more than 7 years ago | (#18339391)

Then we should have nuclear power behind all those 220v outlets... and 90% of cars should be much smaller,

Exactly. During the summer when the grids are already at full capacity it would be a very bad idea to have hundreds of thousands of electric cars charging at the same time. Then you won't pay your hard earned $$$ to BP or Exxon but instead to power companies like Enron. We actually need two things - 1) more energy and 2) a good way to store it (this implies a safe and economical way to distribute it as well...). It would also be nice not to make much of a mess in the process. Nuclear power seems like the way to go. In US they have not build a nuclear power plant in ages instead they burn tons and tons of coal that ironically enough releases a lot more radio-isotopes into the environment than nuclear power plants would, not to mention other more obvious pollutants. Check this [] link out.

Re:Not the final solution (1)

inviolet (797804) | more than 7 years ago | (#18339411)

I suppose my first question is, when the owner inevitably lets the ethanol run out, what happens? Can the engine computer dial down the boost enough to prevent detonation? Or does the engine just have to shut down?

Not to worry; for decades now, we've known that water injection can similarly increase the power output (but not the overall efficiency) of an engine.

Re:Not the final solution (1)

jez9999 (618189) | more than 7 years ago | (#18339441)

If you're gonna dream, at least dream of something [] more idealistic, panacea-like, and less complex. :-)

Re:Not the final solution (1)

amigabill (146897) | more than 7 years ago | (#18339475)

plug-in series hybrid with about 60 miles of electric-only range and the ability to run maybe 400 more with the engine providing generator power.

And have inductive field charging pads built into parking lot spaces which can be used to recharge the battery without having to plug in a cord. Have some RFID or other form of automatic vehicle and/or account identification which can enable/disable the charging pad depending on payment authorization if it's a commercial charging configuration and to monitor battery health and other interesting data. Could be useful for companies with fleets of such cars so workers don't forget to plug them in between uses, so you don't forget to unplug the thing when you leave and tear something apart or hurt anyone, etc.

Hopefully this can be considered prior art publication in case some nut job tries to patent the idea and rip us all off later.

Re:Not the final solution (4, Interesting)

Rei (128717) | more than 7 years ago | (#18339805)

and 90% of cars should be much smaller,

Americans would never accept that. You might as well just say "and fairy princesses should fly down from candyland and give us all ponies to ride."

I think a more realistic possibility is that vehicles will just get much lighter. As an example, if Boeing can make the Dreamliner out of carbon fibre, perhaps it's not that long before we start seing reasonably priced, mass-produced carbon fibre car bodies. There's also reasonably good odds of significant price reduction in titanium and titanium alloys, and aluminium use is becoming more widespread in the automotive industry.

My ideal "dream" situation? A "grid" transportation system, in which vehicles are networked together without any humans behind the wheel (except "offroad"). electric vehicles which get their power from the road (standing wave transmission, perhaps). Autoconvoying and optimized speeds to greatly reduce traffic, increase road capacity, and reduce wind resistance. With vehicles much lighter from being pure-electric without need for even carrying the power source, high speed "bulletways" with coils of wire embedded in them, so that vehicles with halbach arrays (magnetic arrays with highly lopsided fields -- near double-strength on one side, near zero on the other) can employ "Inductrac" style maglev, eliminating rolling losses and having very little maglev losses at high speeds.

  * Greatly reduced wind resistance and no rolling losses.
  * Still your own, personal vehicle (the profiles would likely be a bit different from present day for optimal convoying, though)
  * Never having to drive. Play, sleep, work, chat, whatever during the trip.
  * Less need for roads eating up cityspace
  * Less traffic
  * Much faster travel, to the degree that airlines would be needed much less often.
  * Much less energy use
  * Independent of oil.
  * No need to even be in your vehicle while it's moving -- automated delivery, automated pickup of your kids or groceries (if the store will load for you), etc.
  * The great economic benefits of travel being automated and fast.
  * Much less space used up downtown for parking, as vehicles can drive themselves to and from less convenient parking without you.
  * No speeding tickets
  * Very few accidents (no human error, no drunk driving, etc)

The benefits go on, and on, and on. Unfortunately, we have all of our existing infrastructure to deal with. Thankfully, it can be moved towards in stages. First hybrids, then plugin hybrids, then electrics, then grid-power electrics. First radar-assisted braking (like we have now), then wireless transponders to assist traffic, then increasing wireless information exchange and planning. Once vehicles are light enough, all-electric, and are designed for high-speeds with automated operation, inductrac-style maglev becomes realistic for long stretches.

Why stick with petrol? (4, Interesting)

shplorb (24647) | more than 7 years ago | (#18339067)

This sounds an awful lot like a modern diesel engine. Modern diesels are turbocharged and use common-rail injection to achieve insane pressures at the injector heads (for really fine atomisation of the fuel), which directly inject into the cylinder. I believe the newer engines even stagger the injection during the compression and combustion cycles too to achieve more power and cleaner burning.

(NB: I'm not a revhead so I might be talking shit)

Re:Why stick with petrol? (4, Informative)

drinkypoo (153816) | more than 7 years ago | (#18339341)

You're correct about all that, but the insanely high pressure is probably as much about getting the fuel into the chamber as it is about proper atomization. See, in a gasoline engine the fuel is [typically] drawn in with the intake air charge, although they are using direct injection sometimes as well. But in a diesel the ignition timing is controlled by injection timing. Diesels are typically over 17:1 compression - my Mercedes (currently defunct) is 22:1, PLUS an 11 PSI turbocharger. So you need considerable pressure just to get the fuel into the chamber. My Mercedes is old-school, it uses indirect injection (think CVCC, it's got a prechamber) but it also uses a mechanical injection pump that basically consists of a cam that runs five cylinder-type pumps (think hydraulics) and is driven by a connection to the crankshaft.

Still using fossil fuel (1)

fishdan (569872) | more than 7 years ago | (#18339071)

I'm not an eco guy by any stretch of the imagination, e.g. I still have an open mind about the cause of global warming. But I definitely believe what they said in Who killed The Electric Car [] : With at least $1 Trillion worth of oil in the ground, the oil industry will do ANYTHING to prevent people from finding an alternative source of energy.

Even promoting more efficient cars.

Re:Still using fossil fuel (1)

EriDay (679359) | more than 7 years ago | (#18339747)

Times have changed since 1996. GM and Ford have spun off Delphi and Visteon. In 1996 the automakers controlled the entire automotive supply chain. Fast forward 10 years and we have Tesla assembling cars from OEM parts. A small cabal of automakers and oil companies can no longer squelch the electric car.

not power, efficiency (1)

fred fleenblat (463628) | more than 7 years ago | (#18339125)

There really isn't a shortage of power in modern car engines. What we need is efficiency, and not mere volumetric efficiency at that. The article implies that a smaller engine would be more efficient since it could be lighter, but even if knock is controlled, it will have to be a very stout block with either heavy components (rpm limiting) or expensive titanium components. Knock isn't the only thing that wears/damages a high performance engine. Heat (and heat cycling), friction, and lubrication all have to be carefully managed.

Re:not power, efficiency (1)

drinkypoo (153816) | more than 7 years ago | (#18339435)

It doesn't have to have heavy components. They could be forged aluminum :) That's significantly more expensive than steel, but a lot cheaper than Ti. And in quantity they wouldn't be nearly as expensive as the aftermarket performance parts typically available. Modern engines are already specifying higher grades of oil and coolant than have been common.

I don't get it (3, Interesting)

roman_mir (125474) | more than 7 years ago | (#18339127)

How do we go from this:

A vehicle that used this approach would operate around 25 percent more efficiently than a vehicle with a conventional engine.

to this: ...Cohn and his colleagues have created a design that they believe could triple the power of a test engine, an advance that could allow automakers to convert small engines designed for economy cars into muscular engines with more than enough power for SUVs or sports cars.

does a 25% increase in efficiency translate into tripling the power output?

Re:I don't get it (1)

johnny cashed (590023) | more than 7 years ago | (#18339169)

'cause it has ethanol in it. It is the latest eco-buzzword! It will cure all our problems!

Re:I don't get it (1)

AP2k (991160) | more than 7 years ago | (#18339185)

Efficiency and power are not the same. If a 200 hp engine consumed 20 mpg, an increase of that nature would yeild 600 hp and 15 mpg.

Re:I don't get it (3, Informative)

dal20402 (895630) | more than 7 years ago | (#18339215)

Yes. Note that I don't actually believe the claim about tripling power, at least not with a whole lot of *very heavy* reinforcement of the block and heads.

For example: (Note: Numbers strictly pulled out of ass.)

2.4l conventional engine: 150 hp, 30 mpg

2.4l Super-Mega-Monster-Gas-TDI-Ethanol engine: 450 hp, 12.5 mpg

Your engine is 25% more efficient per hp and is generating 3x as much power.

Of course, the real application they have in mind is to create reinforced motorcycle-size engines that can power sedans, or small car motors that can power SUVs. If your 2.0l engine can create 360 hp, big torque, and get 17-18 mpg, you've reinvented a turbodiesel, except that your engine is (even with reinforcements) way smaller and lighter.

Re:I don't get it (1)

roman_mir (125474) | more than 7 years ago | (#18339541)

2.4l conventional engine: 150 hp, 30 mpg

2.4l Super-Mega-Monster-Gas-TDI-Ethanol engine: 450 hp, 12.5 mpg
- that's the part I don't get. Is there a dependency between efficiency and power output? I don't see it. They are saying that by increasing efficiency by 25% they are tripling the power output.

and by the way I don't think it's 150hp, 30mpg to 450hp, 12.5 mpg. It sounds more like 150hp 30mpg to 450hp 22.5mpg, but this can't be right, when the power tripples, the mpg has to be calculated from that trippled power.

It's as if the engine normally running at 150hp, 30mpg was forced to give 450hp, probably at 10mpg, but would be more efficient at that power output by 25% (your 12.5mpg.) I don't know, it sounds iffy, I can't believe a 25% efficiency increase allows engine to triple power output.

Re:I don't get it (1)

maxume (22995) | more than 7 years ago | (#18339339)

Nothing translates, but it is a double plus good. The energy you can produce with an engine is roughly limited by how much fuel you can burn, which is roughly limited by how much air you can push through it. Limiting pre ignition means you can run at higher pressures, which helps with efficiency and lets you push more fuel through a smaller engine.

Re:I don't get it (0)

Anonymous Coward | more than 7 years ago | (#18339457)

You're confusing 'Power/EngineSize', and efficiency (Power/FuelConsumption).

Some of the rotary engines (found in the Mazda RX-7 and RX-8) have *tiny* engines (and substantial power), but still only marginal efficiencies.

Re:I don't get it (1)

TigerNut (718742) | more than 7 years ago | (#18339899)

The efficiency gain is obrained by using the exhaust heat energy to compress the incoming air and thereby get more air into the engine, which increases power output. The increased power output requires added fuel (as well as the added air) but essentially, more of the available energy is extracted from the fuel before the exhaust is dumped overboard.

Typical gasoline engines are about 30% efficient from a heat standpoint: 30% of the chemical energy in the fuel is converted to torque at the flywheel. The remainder of the energy is more or less evenly split between the coolant and the exhaust. If the turbocharger were to extract half the available energy in the exhaust stream and use it to compress the incoming air, then that would give you a 25% increase in energy efficiency. The absolute air pressure (at sea level) is about 14 PSI. Using a turbocharger to double the intake air pressure would at least double the engine's power because it's also overcoming pumping losses in the process. Using ethanol or methanol evaporation to cool the intake charge boosts the air density while also adding to the fuel and oxygen dumped into the combustion chamber, so it's a double win. An intercooler would do the same (increasing charge density) but not add any fuel to the mix, and the heat rejected by the intercooler is dumped overboard. THe heat added to the ethanol/methanol gets recycled back out the exhaust.

Since when is this news (2, Interesting)

Ninety-9 SE-L (1052214) | more than 7 years ago | (#18339171)

Um, we figured this out decades ago. Race engines types of higher octane solutions to raise boost and compression. Methanol, Ethanol, Alcohol, Race fuel. It's simple chemistry. Pure gasoline packs more energy but is unstable, additives like Ethanol raise octane ratings making the fuel more stable but packing less punch (energy per volume of fuel). E85 is equivalent to 108-116 octane, good stuff, but not for a Buick. Throw it into a regular car and you need to suck down more fuel to get the same output, however, throw it into a high compression or high boost engine, and you can more effectively make power. High compression engines are definitely more efficient, ask me how I know. I run 12:1 on 93 octane and get 37MPG on the highway, my car also runs 13s at the track. Before I went high compression, I made about 30MPG on 87 Octane. Calculate this out and I save money even though I'm paying 20c more per gallon. This is racing technology and it's not even remotely new. The only thing that's new is E85 is available at more places and cars are being set up to run E85. If you put E85 in a regular car, you're an idiot. If you buy a car that's supposed to run E85, make sure that it's set up to make the most out of the fuel and never go back to standard gasoline.

Re:Since when is this news (1)

spun (1352) | more than 7 years ago | (#18339463)

Yeah, we've been keeping ethanol in a separate tank from gasoline and injecting it separately and directly into the cylinders to cool them and prevent knock forever. Riiiiight.

You should really read the article before making snide comments meant to demonstrate your superior knowledge of a topic.

Re:Since when is this news (2, Insightful)

Andy_R (114137) | more than 7 years ago | (#18339539)

The difference between this idea and simply mixing ethanol into the petrol is that the ethanol is injected first, so it vapourises, cooling the compression chamber down, in a similar way to a water injection intercooler. Quite how they arrive at a huge power gain from this isn't adequately explained though, and they do seem to ignore the difficulties of strengthening an engine enough to cope with triple the power, and a few thousand freeze/thaw cycles per second, and the extra weight that's going to add.

Getting a lot of power from a small engine isn't very difficult, the Brabus tuned version of my Smart Roadster (review here [] ) gets over 100bhp from a sub 0.7 l engine, and my less tuned 80bhp version give me about 60 mpg (and thats using our smaller british gallons!). The downside is you don't get lots of torque, which is why you'll only find this engine in a light sporty car, not an SUV.

These guys are really on to something (1)

codepunk (167897) | more than 7 years ago | (#18339175)

Wow these guys should sell this technology to the drag racing community...oh wait they have been burning alcohol for years to give them the ability to, reduce intake charge temperatures, reduce pre-ignition in high compression and large boost scenarios.

Yes we should be burning more ethanol and it is a outstanding engine fuel however pre-blending by the oil companies is a crappy idea. How about blending the fuel at the pump so I can buy pure ethanol and or blended. If one could buy pure ethanol at the pump then those of us that wanted to take advantage of high compression engines with insane boost pressures could do it, and those that wanted to run 15% passenger car run of the mill under powered plants could do the same.

Anyone got a link to an actual article? (0)

Anonymous Coward | more than 7 years ago | (#18339249)

No, not the PR summary, which seems to suggest that direct injection (into the cylinder, not outside like a standard MPFI system) was new. There's a clue here:

But Cohn and his colleagues found that if ethanol is introduced into the combustion chamber at just the right moment through the relatively new technology of direct injection, it keeps the temperature down, preventing spontaneous combustion.
...but no more.

So we know that we're talking exclusively about ethanol, but don't know anything about any claimed performance or efficiency gains. If I was trying to quantify the benefits of something and just said "would be a rocket with our technology" I'd expect to get a kick up the arse and a suggestion to try again. Presumably, since MIT is an academic institution there is something actually written up somewhere?

BMW N54 (1)

KrisJon (6582) | more than 7 years ago | (#18339291)

Aside from the ethanol bit, BMW already uses direct injection and turbocharging to get 300hp, 300ft-lb and 30 MPG (highway) out of a 3 liter I6. N54 engine from the 2007 335: 144546 []

Kids and car enthusiasts did this decades ago (2, Interesting)

Oz0ne (13272) | more than 7 years ago | (#18339293)

Seriously. Direct injection, fine tuned control of timing, and turbo charging all put together is what you see in a large number of hobbiest race cars. Drag, autocross, whatever. A lot of times they'll skimp on tolerances thus reducing the reliability of the engine, but it's not at all uncommon to take a solid normally aspirated engine and triple it's output with some good planning and bit of machine work.

I've personally never added a turbo where there wasn't one before, but I HAVE done machine work, timing work, and injector work. I've taken a car from 220 hp to 290 hp with no detriment to the mileage, just better fuel/air mixtures and precise timing. It doesn't surprise me at all that people who've actually studied combustion instead of working on it for fun have been able to triple the output.

What's surprising is how inneficiently tuned a lot of engines come from the factory.

I wonder... (1, Funny)

Anonymous Coward | more than 7 years ago | (#18339295)

if it will become the next redneck toy to show off at the Burger King's parking lot.

Meh, they'll stick to the neon lights.

Re:I wonder... (1)

dal20402 (895630) | more than 7 years ago | (#18339709)

Man, you haven't been in enough Burger King parking lots.

*Rednecks* would rip the neon right off the car. They're more interested in oversized tires, big loud ugly intake/exhaust components, and torn seats.

*Ricers* put on neon, and fart cans, and decals. Lots of decals.

Oh, and the rednecks are modifying pickups, old Detroit iron, and (when they somehow stumble across money) '90s Camaros. The ricers are modifying Civics and Corollas, mostly.

Audi A3 (1)

neurosis101 (692250) | more than 7 years ago | (#18339301)

How about the Audi A3 2.0T? Direct injection from Audi's R8 racing technology and turbocharged too.

Congrats to MIT for discovering already in use technology!

Then again, maybe its new to them because Americans don't like LeMans?

MIT guys!! (1)

eclectro (227083) | more than 7 years ago | (#18339307)

Please drop your internal combustion research. This is a dead-end technology that relies on us burning stuff that we buy from terrorists. Please focus your efforts on a fusion engine that uses garbage like in the movies. The flying car part can wait though. Just get the fusion engine going. Thanks.

Re:MIT guys!! (1)

jelizondo (183861) | more than 7 years ago | (#18339893)

Not every oil-producing country is infested with so-called terrorists.

The U.S. buys a large part of its oil from México, for example.

Don't buy the fascist rhetoric pal.

New Technology (1)

frosty_tsm (933163) | more than 7 years ago | (#18339377)

Do you really think that the Big Three will adopt new engine technology?

You can still find push-rod engines being built today...

Re:New Technology (1)

confused one (671304) | more than 7 years ago | (#18339659)

I know it's /. but...

if you rtfa, you'd see that Ford is testing it.

Re:New Technology (0)

Anonymous Coward | more than 7 years ago | (#18339743)

Depends who you think the "big three" are...

BMW, Audi and Mercedes have been doing direct injection for a while, and I hear small, turbocharged engines are pretty popular in Japan.

Re:New Technology (1)

zzatz (965857) | more than 7 years ago | (#18339847)

DC, Ford, and GM already sell engines using direct injection.

US automakers do have management problems, but technology is not one of them. Quality levels are actually better than most European and some Japanese competitors, but are sadly sabotaged by incompetent dealerships. The UAW remains a huge problem; the leadership would like to take the steps needed to save good jobs for the long run, but the membership will toss out anyone who tries. Health care costs are out of control. And so on...

It could be worse. Ford looks good compared to FIAT.

Hardware: A New Lease On Internal Combusiton (1)

DuckByte (1075341) | more than 7 years ago | (#18339439)

With all the new technology constantly being tested by the auto racing community, it's hard to believe that any "breakthru" could truly produce such a large increase in horsepower. The Formula One teams spend hundreds of millions of dollars for modest increases in performance. If it were taht easy, it would have been done already.

Turbo lag, premature combustion (2, Informative)

hcdejong (561314) | more than 7 years ago | (#18339469)

If they use this to increase turbocharger pressure, I'd expect turbo lag [1] to become a problem again. It'd be better to increase the compression ratio instead. Or maybe combine ethanol injection with some of the variable-compression designs that have been surfacing lately.

Also: why would premature combustion still be a problem in a direct-injection engine? It should be possible to inject the fuel when it is needed, and not before. Or would that lead to timing problems?

1: turbo lag is the delay between pressing the accelerator and power output rising. It's affected by the size of the turbocharger, boost pressure and a few less important factors.

CSIRO have researched this (1)

EEPROMS (889169) | more than 7 years ago | (#18339581)

I listened to a CSIRO podcast about this about 6 months ago. With normal combustion as you increase the pressure you also increase the problem of early ignition (knock) due to a side effect of the temperature increasing. What they found out was if you add ethanol it has a "cooling" effect to the combustion chamber thus allowing you to increase the pressure in the combustion chamber. For auto makers this means they can use smaller lighter motors in a car to gain the same amount of power output.

Re:CSIRO have researched this (1)

EEPROMS (889169) | more than 7 years ago | (#18339727)

Sorry I missed a bit, what the study actually found was how little ethanol you needed, you can have a small tank (around 10 litres) and it would last 3 months on a single refill for the average commuter, but the engine could have 2 times to 4 times the power to weight ratio.

Audi RS4 (3, Informative)

mihalis (28146) | more than 7 years ago | (#18339611)

Audi already uses direct injection and uses a compression ratio of 12.5:1 in its 4.2 liter v8 achieving 100 horsepower/liter without a turbocharger, see 2007 Audi RS4 review at Edmunds.COM []

I'm intrigued to imagine what they could do if this ethanol based charge cooling works out. I'm already forced to put 15% ethanol in my Audi V8 (sadly NOT an RS4), living in NYC, but if this works out maybe I can support the farmers AND have a powerful car for the weekends (I commute on the subway).

Buy a direct injection turbo charged car today! (3, Insightful)

Spoke (6112) | more than 7 years ago | (#18339691)

People have long known that ethanol fuels have high octane ratings (the measure of how knock resistant a fuel is).

People have also long known that turbo charging an engine is a great way to extract more power out of a small engine.

People have also known that direct injection allows you to reduce the tendency to knock since it lets you inject fuel into the hot engine at the very last second - reducing the amount of time the air/fuel mixture has to heat up.

And guess what? Mazda produces cars today that has both direct injection and is turbo charged. For example, the MazdaSpeed 3 [] .

It's 2.3 liter engine produces 263hp and 280lb/ft of torque and has an EPA fuel economy rating of 20/28mpg. So yes, while it does provide good power and decent gas mileage, it's nothing earth shattering compared to turbocharged cars without direct injection.

The engine has a very high compression ratio for a turbo charged gasoline engine (9.5:1), especially one that pushes over 15psi of boost into the cylinders. That is direct injection working for you.

For example, the slightly bigger turbo charged 2.5 liter Subaru WRX engine has a compression ratio of 8.4:1 and maximum boost of 11.6psi is rated at 230hp/235lb/ft of torque (though it is admittedly underrated) with similar fuel economy as the Mazdaspeed 3 considering that it is all-wheel-drive (20/26mpg EPA). The more powerful WRX STi has the same 2.5l displacement, 8.2:1 compression ratio and a bigger turbo pushing 14.5 psi is rated at 293hp/290lb/ft of torque but less fuel economy, 18/24mpg.

Unless there is a lot of potential still to be found by combining these 2 technologies, I see it as more of an evolution rather than a revolution. Perhaps a 1.0 liter engine would be able to muster 120+ hp/torque but I find it hard to believe that it could achieve mileage ratings significantly higher than a hybrid. And you still can't turn the engine off when idling or coasting down hill.

So how about a direct-injection, turbo-charged, atkinson cycle hybrid and combine the best of all technologies?

Erm.. Audi? (1)

bmajik (96670) | more than 7 years ago | (#18339723)

You can go buy an engine right now that uses turbocharging, high static compression, and direct injection. The Audi 2.0T FSI engine, featured in the A3, A4, VW Jetta, and VW Passat feature this.

Ethanol is an octane enhancer (which prevents pre-ignition), and lets you run either higher boost, higher static compression, or more ignition advance.. all of which make more power (or more efficiency), and none of which, even in combination, will triple the output OR fuel economy. Many auto enthusiasts are discovering the benefits of running E85 in their modified turbo charged cars, since it is effectively 104 octane fuel, but at normal fuel prices. Ethanol also burns cooler than gasoline so is especially nice on turbocharged engines where unrecaptured heat and absolute exhaust temperatures are your enemy.

you dopes (0)

Anonymous Coward | more than 7 years ago | (#18339733)

Wow, you dipshits know everything.....why are folks even bothering to go to MIT!?!?!

Knock sensors and computers don't add power, they give the engine as much advance as it can take short of detonation.

This sort of setup will inject a cooling shot of alcohol AT THE PRECISE BEST TIME (unlike the WWII fighters which just poured it on like some nitro funny car's MECHANICAL injection)

This is a good idea which MIGHT make a very measurable difference in future cars.....


This is not news, or a discovery. (3, Insightful)

a4r6 (978521) | more than 7 years ago | (#18339751)

For anyone that knows their stuff about car engines, this article is a joke.

Both turbocharging and direct injection are preexisting technologies, and neither looks particularly impressive. Indeed, used separately, they would lead to only marginal improvements in the performance of an internal-combustion engine.
Really? So there aren't people slapping large turbochargers on little 3 liter supra engines and increasing the engine output 5-fold? Or is that only marginal?

That aside, the problem with this is that a turbocharged engine at full output is very inefficient. A larger naturally aspirated engine will always be more efficient than the small turbocharged engine of the same maximum output. That's because a lot of energy is wasted compressing the intake charge, more than can be made up for with the displacement decrease, even with the newest fanciest garrett turbos. The only merit efficiency-wise of turbo engines is engine efficiency at low loads (when the engine is not under boost) relative to the maximum output. There is obviously a balance to be struck here, and that's why 18 wheelers have big v8's with turbo chargers, rather than even bigger engines or smaller engines running under high pressure. Designing a motor vehicle is always a balancing act, and in most cases a turbo is not helpful because of the cost, reliability and other shortcomings versus the benefits.

Recently, car makers have started using direct injection to combat preignition that can damage an engine. It allows them to run leaner fuel mixtures, higher compression and more aggressive spark timing, improving the power/efficiency of engines. Direct injection has the exact same benefit with turbocharging. There are no compounded benefits from mixing the two technologies.

Equivalent (but inferior) to WATER injection. (2, Insightful)

Ungrounded Lightning (62228) | more than 7 years ago | (#18339865)

Turbocharging already gives about a 2-to-1 boost while avoiding the knock limits - and it doesn't require a second tank, just higher-octane gas (which, at current price levels, doesn't command all that high a cost premium over regular). So the claimed 3-to-1 boost, while a significant further improvement worth going after, isn't as big a jolt as the standalone description would make you think.

(My commuting vehicle is a 4-cylinder turbo - and 15 years old. It has 100k miles on it and I'm rebuilding the vehicle around it at a cost of about 8 grand - suspension, tranny, major engine service - because I can't get an equivalently performing vehicle on the current new market at any reasonable price. That's apparently because adding a turbo to a small passenger car has enough downsides that the public isn't interested. (Or perhaps because the auto companies' marketing departments are totally clueless.))

Direct WATER injection of a high-compression ALSO gets this 3-to-1 or better boost. It has the same advantages as the alcohol injection at less cost: Higher power, reduced preignition, etc. But you can go even farther, since water won't, itself, combust.

You also get more efficient transfer of heat to mechanical advantage by using the vaporization of the water powered by the heat of the regular fuel.

And water is easier to find and cheaper than ethanol when it comes time to refil the second tank.

This has been well known for a long time.

The reason it hasn't been built into production engines so far: It requires two tanks of consumables. Run out of one and the engine has to stop, or run in a degraded mode. Auto makers haven't wanted to add that sort of operational complexity due to liability and consumer satisfaction issues.

This "new" idea has the same drawback, only moreso, since the second consumable liquid is less generally available and already highly regulated.

= = = =

On the other hand, we've now got much more flexible computerized control of the engine. With the compression boost provided by a turbo (which can be disabled by software control if the alcohol or water runs out), a car with an empty second-fuel tank can still run while meeting emission requirements and without self-damage. You'd lose 2/3 of your peak power and your MPG would drop. But the car would remain legal, street-legal, and unharmed.

So perhaps it's time to revisit direct cooling-fluid injection, dual-consumable, internal combustion engines.

But if so, unless research shows that ethanol has some BIG advantage over water, using water would have the advantage that you don't need to modify the support infrastructure.
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