Mazda Develops Engine That Is up to 30 Percent More Fuel Efficient

Megalith

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Mazda has made a breakthrough in long-coveted engine technology: the automaker will be offering the world’s first compression injection gasoline engine, the SKYACTIV-X. These engines will utilize a technology dubbed Spark Controlled Compression Ignition, which takes a page out of diesel systems by relying on compression rather than spark plugs to ignite petrol. The X line will use between 20 and 30 percent less fuel, and some claim that these engines will be cleaner than electric.

"We think it is an imperative and fundamental job for us to pursue the ideal internal combustion engine," Mazda R&D head Kiyoshi Fujiwara told reporters. "Electrification is necessary but... the internal combustion engine should come first." A homogeneous charge compression ignition (HCCI) engine ignites petrol through compression, eliminating spark plugs. Its fuel economy potentially matches that of a diesel engine without high emissions of nitrogen oxides or sooty particulates.
 
So how many more miles per gallon does this translate into? article didn't say
 
Very interesting and exciting.

I wonder how they are going to keep the fuel injection pumps from dying. Diesel lubricates pretty well while gasoline does not.

You are also going to have to have much tighter tolerances with gasoline as it is much thinner than diesel.
 
https://en.wikipedia.org/wiki/Homogeneous_charge_compression_ignition

Stratified charge compression ignition also relies on temperature and density increase resulting from compression. However, it injects fuel later, during the compression stroke. Combustion occurs at the boundary of the fuel and air, producing higher emissions, but allowing a leaner and higher compression burn, producing greater efficiency.
HCCI engines achieve extremely low levels of Oxides of Nitrogen emissions (NOx) without a catalytic converter. Hydrocarbons (unburnt fuels and oils) and carbon monoxide emissions still require treatment to meet automotive emission regulations.
 
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I manage to get about 28-32 highway on my 2016 Mazda 6 so this is great news. As much as I want a Tesla, the new one just looks awful and I am not in Model X level of income bracket.
 
Who knows if this will ever make it to a regular car like the rotary engine or laser ignition.
 
I manage to get about 28-32 highway on my 2016 Mazda 6 so this is great news. As much as I want a Tesla, the new one just looks awful and I am not in Model X level of income bracket.

I could do that with an 6.0L LS2 based GTO back in 2005. It's funny that we think we've come so far but we really haven't come as far as we think on the efficiency front. Certainly, we've been able to get a lot more performance for the same fuel, but efficiency itself has been more or less stagnant with the internal combustion engine for more than a decade.
 
I could do that with an 6.0L LS2 based GTO back in 2005. It's funny that we think we've come so far but we really haven't come as far as we think on the efficiency front. Certainly, we've been able to get a lot more performance for the same fuel, but efficiency itself has been more or less stagnant with the internal combustion engine for more than a decade.

Market fixing and stagnation has gotten to the point where no other competitor has cared about efficiency. It wasn't until Tesla started to light a fire under their ass that car makers have decided to actually try something new instead of releasing a fancy new shell over the same old guts. There's just no incentive to keep our air clean and our wallets full. Just look at all the shit you have to go through to get solar panels in some states.
 
The X line will use between 20 and 30 percent less fuel, and some claim that these engines will be cleaner than electric.

I assume they mean the oil lobbyist who was sitting at the bar?

Assuming the factories producing the vehicles are equal (so we don't get into the "supply chain is cleaner!" talk), electric vehicles can be charged on cleaner sources of energy. Oil vehicles can not, no matter what, they must burn a fuel.

Btw, I'd guess that 20-30% more efficient implies it's more efficient than a traditional engine in the same vehicle. So if the car gets 28mpg, it'd now get 35mpg (splitting the difference of the estimate).
 
I assume they mean the oil lobbyist who was sitting at the bar?

Assuming the factories producing the vehicles are equal (so we don't get into the "supply chain is cleaner!" talk), electric vehicles can be charged on cleaner sources of energy. Oil vehicles can not, no matter what, they must burn a fuel.

Btw, I'd guess that 20-30% more efficient implies it's more efficient than a traditional engine in the same vehicle. So if the car gets 28mpg, it'd now get 35mpg (splitting the difference of the estimate).

Probably.
 
I know they won't but I hope that Mazda uses this tech to make a 300HP V6 for the Mazda6 that gets the same MPG as an I-4. I LOVE my 3.7L V6 Mazda6. It is a blast to drive. The new Skyactive 2.5L I-4 Mazda 6's leave a lot to be desired.

BTW, Mazda's Skyactive Diesels are really interesting too. They have a 16:1 CR (low for a diesel) and they rev to 5500rpm (high for a diesel). Too bad they won't make it in to the Mazda 6 either.
 
Mazda tech news is meaningless until it shows up on the dealer lot. Diesel was supposed to be out in 2011... Also no RX7 no care.
 
Unless you are of the 6% of the US that is powered by hydro, solar or wind, your electricity is being made by either coal, natural gas, or nuclear. There is a lot of conversion loss when using electricity. First at the turbine, then at the step up transformer, then line loss, the step down transformer to your home, the inverter/charger to charge your car, then the inverter to the electric motor(s) in your car. What Mazda is saying is that it's more efficient to burn the fuel directly under your hood than to use electricity made 50 miles away.
 
I assume they mean the oil lobbyist who was sitting at the bar?

Assuming the factories producing the vehicles are equal (so we don't get into the "supply chain is cleaner!" talk), electric vehicles can be charged on cleaner sources of energy. Oil vehicles can not, no matter what, they must burn a fuel.

Btw, I'd guess that 20-30% more efficient implies it's more efficient than a traditional engine in the same vehicle. So if the car gets 28mpg, it'd now get 35mpg (splitting the difference of the estimate).

Beat me to it.
 
I think the most interesting part of the report is : "Mazda executives cited a forecast saying that 85% of vehicles sold in 2035 will still use internal combustion engines, as a greater share of car sales will come from developing countries that have little or no infrastructure for electric vehicles, such as charging stations and extensive power networks."
 
I think the most interesting part of the report is : "Mazda executives cited a forecast saying that 85% of vehicles sold in 2035 will still use internal combustion engines, as a greater share of car sales will come from developing countries that have little or no infrastructure for electric vehicles, such as charging stations and extensive power networks."

Yea, while first world nations go clean, the rest of the world is just entering their industrial ages... the irony.
 
Mazda tech news is meaningless until it shows up on the dealer lot. Diesel was supposed to be out in 2011... Also no RX7 no care.

To be fair, they thought they'd be able to get their diesel into the US without needing urea injection because VW had managed to do it. But they never could get it to meet emissions targets and were left wondering how VW did it. We know how that turned out.
 
I could do that with an 6.0L LS2 based GTO back in 2005. It's funny that we think we've come so far but we really haven't come as far as we think on the efficiency front. Certainly, we've been able to get a lot more performance for the same fuel, but efficiency itself has been more or less stagnant with the internal combustion engine for more than a decade.
You could do that on the hwy in your overdrive gear, same with almost all LSx vehicles. Compare the city numbers and I bet there would be a bit more of a discrepancy.

As far as the efficiency stagnation, kind of... ICE has been stuck at around the 20-30% mark.

One reason we haven't seen large jumps in fuel economy is that much has changed over the past several decades, mainly emissions/safety, which make fuel economy a difficult needle to move. Many like to point at the claimed 57mpg of the 1987 CRX HF, but fail to realize compared to the modern counterpart they are completely different animals. A current Honda will be much heavier, make more power, output less emissions, etc. Also note how testing methodologies have changed over the years for more accurate MPG estimates.

So has MPG stagnated? Yes, but not as much as one thinks.
 
Who knows if this will ever make it to a regular car like the rotary engine or laser ignition.

Actually, Mazda is the same company that has produced and still researches Wankle rotary engines.

"Mazda of Japan ceased production of direct drive Wankel engines with their model range in 2012, leaving the motor industry worldwide with no production cars using the engine. The company is continuing development of the next generation of their Wankel engines, the SkyActiv-R, with a new rear-wheel-drive sports car model announced in October 2015, although the launch date is not until 2020."

https://en.wikipedia.org/wiki/Wankel_engine
 
Actually, Mazda is the same company that has produced and still researches Wankle rotary engines.

"Mazda of Japan ceased production of direct drive Wankel engines with their model range in 2012, leaving the motor industry worldwide with no production cars using the engine. The company is continuing development of the next generation of their Wankel engines, the SkyActiv-R, with a new rear-wheel-drive sports car model announced in October 2015, although the launch date is not until 2020."

https://en.wikipedia.org/wiki/Wankel_engine

Omg, did not know that?
 
Unless you are of the 6% of the US that is powered by hydro, solar or wind, your electricity is being made by either coal, natural gas, or nuclear. There is a lot of conversion loss when using electricity. First at the turbine, then at the step up transformer, then line loss, the step down transformer to your home, the inverter/charger to charge your car, then the inverter to the electric motor(s) in your car. What Mazda is saying is that it's more efficient to burn the fuel directly under your hood than to use electricity made 50 miles away.

It's much preferred to be burning that fuel 50 miles away from where people live. The term shitting in your own nest comes to light. There's more to it, just think of one source away from populations as opposed to thousands of mobile sources crapping all over the suburbs.
 
So how many more miles per gallon does this translate into? article didn't say

That depends on the motor and car it is in, what it means is take a given car out of their line up and put in this new motor and you can add "up to" 30% higher mpg.

You are also going to have to have much tighter tolerances with gasoline as it is much thinner than diesel.

Tighter tolerances where and for what? Outside of the actual squish area nothing would change. And viscosity has what to do with it?

Who knows if this will ever make it to a regular car like the rotary engine or laser ignition.

Assuming it works, there would be no reason not to. Mazda wants to meet all the new regulations the US and EU have and being a smaller car company they don't have EVs to offset their normal sales like most of the big names, that mostly sell them for a big offset. Mazda has said they have no plans for an EV or the like platform and are waiting for a "winner" to come out by someone else and base a car off of it's platform. Much like the engine/drivetrain sharing Mazda and Ford do right now.

You could do that on the hwy in your overdrive gear, same with almost all LSx vehicles. Compare the city numbers and I bet there would be a bit more of a discrepancy.

As far as the efficiency stagnation, kind of... ICE has been stuck at around the 20-30% mark.

One reason we haven't seen large jumps in fuel economy is that much has changed over the past several decades, mainly emissions/safety, which make fuel economy a difficult needle to move. Many like to point at the claimed 57mpg of the 1987 CRX HF, but fail to realize compared to the modern counterpart they are completely different animals. A current Honda will be much heavier, make more power, output less emissions, etc. Also note how testing methodologies have changed over the years for more accurate MPG estimates.

So has MPG stagnated? Yes, but not as much as one thinks.

Correct. People forget many cars have gained 1,000lbs or MORE in a very short time, and engines that can do super high mpg exist, but you will be hard pressed to get them and also meet current emission regulations and safety requirements.

I have a friend who talked about that with an old MK1 rabbit he had, what he didn't understand was lack of new features and safety and the fact it weighed 1,700lbs while the new one is over 3,000lbs and produces many times the HP.

If people are willing to put up with smaller cars, 70HP and no airbags etc, they can without a doubt have a 80MPG car.
 
PPL don't really want efficiency. Just look at all them Escalades and Suburbans on the road being floored off the line carrying no extra passengers 24/7.
 
I could do that with an 6.0L LS2 based GTO back in 2005. It's funny that we think we've come so far but we really haven't come as far as we think on the efficiency front. Certainly, we've been able to get a lot more performance for the same fuel, but efficiency itself has been more or less stagnant with the internal combustion engine for more than a decade.
Yes...the LS engines can get great highway mileage with proper gearing, but what were you getting in the city?

Also, the 2016 Mazda 6 is rated to get up to 38 MPG on the highway and 26 MPG in the city. I've seen some people get better than this. So NickJames could probably do better with little change in their driving style.

As for what has been dampening our progress in acheiving greater efficiency, I have 3 contributing factors: safety standards, environmental requirements, and ethanol.

Both safety standards and environment requirements have added quite a bit of weight back to our cars. This means engines have to work harder or you need a more powerful engine to do the same amount of work, both cause an increase in fuel consumption. Manufacturers are working with trying to reduce weight by using different materials (aluminum and carbon fiber come to mind), but initial costs and focus (or lack thereof) seem to be hindering the speed of progress.

As for the ethanol, many gas stations only offer ethanol blend nowadays (typically, 10% or less). And not all states require that stations label which fuels have ethanol in them and how much (the closest I have seen are labels that say up to 10% ethanol may be used). Cars that use an ethanol blend vs pure gas get poorer fuel efficiency. Gas that is E10 (10% ethanol, the most common) can, on average, reduce fuel by about 2%-7% and as high as 20%. Add to it that ethanol is hydroscopic, and well...you get the picture.
 
Unless you are of the 6% of the US that is powered by hydro, solar or wind, your electricity is being made by either coal, natural gas, or nuclear. There is a lot of conversion loss when using electricity. First at the turbine, then at the step up transformer, then line loss, the step down transformer to your home, the inverter/charger to charge your car, then the inverter to the electric motor(s) in your car. What Mazda is saying is that it's more efficient to burn the fuel directly under your hood than to use electricity made 50 miles away.

This is something I've wondered for years but haven't spent the time to research. Taking into account the batteries, power conversion/line losses, etc, are electric cars a net win for the environment? And to be fair gasoline also requires fuel trucks and refineries and whatnot. I'm just not sure how it all compares when you put it all together. Obviously electric cuts down on pollution within the city itself/smog and so that alone may be worthwhile.
 
Yes...the LS engines can get great highway mileage with proper gearing, but what were you getting in the city?

Also, the 2016 Mazda 6 is rated to get up to 38 MPG on the highway and 26 MPG in the city. I've seen some people get better than this. So NickJames could probably do better with little change in their driving style.

As for what has been dampening our progress in acheiving greater efficiency, I have 3 contributing factors: safety standards, environmental requirements, and ethanol.

Both safety standards and environment requirements have added quite a bit of weight back to our cars. This means engines have to work harder or you need a more powerful engine to do the same amount of work, both cause an increase in fuel consumption. Manufacturers are working with trying to reduce weight by using different materials (aluminum and carbon fiber come to mind), but initial costs and focus (or lack thereof) seem to be hindering the speed of progress.

As for the ethanol, many gas stations only offer ethanol blend nowadays (typically, 10% or less). And not all states require that stations label which fuels have ethanol in them and how much (the closest I have seen are labels that say up to 10% ethanol may be used). Cars that use an ethanol blend vs pure gas get poorer fuel efficiency. Gas that is E10 (10% ethanol, the most common) can, on average, reduce fuel by about 2%-7% and as high as 20%. Add to it that ethanol is hydroscopic, and well...you get the picture.
Oh I forgot to mention that in my response. Ethanol is great for making power with great knock resistance, but it is not as energy dense as gas.
Omg, did not know that?
Don't forget the miller cycle engine, Mazda likes to play around with odd engines.

They have been trying to make this "gas diesel", high compression on gas, engine for some time.
 
This is something I've wondered for years but haven't spent the time to research. Taking into account the batteries, power conversion/line losses, etc, are electric cars a net win for the environment? And to be fair gasoline also requires fuel trucks and refineries and whatnot. I'm just not sure how it all compares when you put it all together. Obviously electric cuts down on pollution within the city itself/smog and so that alone may be worthwhile.

Research has been done on this, and transport of fuel is factored along with getting it out of the ground and refining, however the mining and effects of the manufacture of lots of battery types is not fully considered or known. But most calculate the "best know" or cleanest methods, of which none are almost ever used. Over all the best I have seen is a break even and that is when you consider an all solar power grid, now, that is all SOLAR, not just renewable, there is a huge difference there, "biomass" is considered a renewable but is more or less burning of wood and paper....Not very clean or efficient. And lots of studies do not factor in the cost or impact of the manufacture of PV panels or turbines etc etc or the batteries required to support those grids.

So from where we sit now, it's about break even at a much higher cost, worse case is it's a negative at a much higher cost. The tech will probably get there some day, but it is no world saving idea many people act like it is, at least not yet.
 
How do you mean? Do you think it was a hoax??

"Design" an engine, make wild claims and never let anyone look at it, then remove world changing engine from car and put it in storage for 23 years....Nah, sounds TOTALLY legit. After he died he left the motor to a close friend who still holds the claims, but refuses to let anyone look at the motor.

The engine by those close enough to have seen it run said it ran on the verge of popping and ALWAYS ran with knock. He also said there was a "radical" in the gas that allowed it to run at those temps, most who saw the motor run said it was nitrous being injected to help cool the chamber and exhaust gasses to keep it from melting walls, and being that it ran super lean emissions would be horrible.
 
"Design" an engine, make wild claims and never let anyone look at it, then remove world changing engine from car and put it in storage for 23 years....Nah, sounds TOTALLY legit. After he died he left the motor to a close friend who still holds the claims, but refuses to let anyone look at the motor.
The engine by those close enough to have seen it run said it ran on the verge of popping and ALWAYS ran with knock. He also said there was a "radical" in the gas that allowed it to run at those temps, most who saw the motor run said it was nitrous being injected to help cool the chamber and exhaust gasses to keep it from melting walls, and being that it ran super lean emissions would be horrible.

Obviously you know know nothing about this issue. Do you even know who Smokey Yunick was? He was far from a con artist.

I've followed this since I first read about it in Hot Rod magazine in 1984. (I still have the magazine issue) Smokey turn over his prototype to GM engineers to drive the car so they could see his claims were true. The GM engineers tried to break the car. Tried to make them over heat, and tried to make the system fail. They could not. NO he would NOT let them take it all apart so they could see how it worked. There were some one-off parts Smokey developed in it. The rest of it could be assembled with off the shelf parts. He was trying to sell the system to GM, (he collaborated with GM for decades developing racing parts) not have them copy it and claim they developed it with a team of 50 lawyers nodding yes.
 
Obviously you know know nothing about this issue. Do you even know who Smokey Yunick is? He is far from a con artist.

I've followed this since I first read about it in Hot Rod magazine in 1984. (I still have the magazine issue) Smokey turn over his prototype to GM engineers to drive the car so they could see his claims were true. The GM engineers tried to break the car. Tried to make them over heat, and tried to make the system fail. They could not. NO he would NOT let them take it all apart so they could see how it worked. There were some one-off parts Smokey developed in it. The rest of it could be assembled with off the shelf parts. He was trying to sell the system to GM, (he collaborated with GM for decades developing racing parts) not have them copy it and claim they developed it with a team of 50 lawyers nodding yes.

You can't seriously be buying into this decades later?
 
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