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Larger displacement Atkinson cycle engines may be in the future for Toyota

A number of automotive manufacturers have begun to move away from larger displacement naturally aspirated engines to smaller displacement turbocharged engines. The general idea was that smaller and lighter engines would use less fuel while offering the same sort of performance thanks to the addition of a turbocharger. However, in the real world many drivers have discovered that turbocharged small displacement engines are often unable to deliver on their fuel efficiency claims.

Toyota is considering bucking the industry trend and rather than going with smaller turbocharged engines, is considering larger naturally aspirated engines to improve fuel efficiency. Senior managing officer in charge of drivetrain R&D for Toyota Koei Saga recently said that Toyota believes gasoline engines could benefit more from upsizing capacity in conjunction with Atkinson combustion cycles than going smaller with turbochargers.
Atkinson engines today are typically only used in hybrid vehicles like the Prius, Ford Fusion Hybrid, Hyundai Sonata Hybrid, and Honda Accord Hybrid.

Toyota Camry
Increasing the displacement of an engine using the Atkinson cycle would deliver a specific output less than that of similarly sized conventional combustion cycle engines, but fuel economy would be better. Toyota believes that fuel economy would be better than the smaller engines they replace.
Toyota has offered no timeframe for bringing larger displacement Atkinson cycle engines to market and hasn't hinted at which models might get the Atkinson cycle engines.
Mazda experimented with similar “delayed valve” Miller Cycle technology over a decade ago in the Millenia midsize sedan. But instead of using electric motors to make up for the reduced power density like today’s Atkinson-engine hybrid vehicles, the Millenia used a supercharger.
Saga also talked a bit about the next generation Toyota Prius saying that the vehicle will use a mixture of battery technology including lithium-ion and nickel batteries. The reason for mixing battery types is that lithium-ion batteries are better for performance, but the durability and lifespan is better for nickel batteries. 

Source: Green Car Reports

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According to whom?
By FITCamaro on 10/16/2013 10:00:07 AM , Rating: 2
However, in the real world many drivers have discovered that turbocharged small displacement engines are often unable to deliver on their fuel efficiency claims.

My 2012 Chevy Cruze Eco more than delivered on its advertised fuel economy. And I attained better than advertised averages on even automatic base LT models.

Maybe some cars haven't delivered on promised fuel economy, but not all. And in the real world some drivers haven't because of their driving habits, not because the car isn't capable of it. Flooring it off lights and doing 85 mph on the freeway isn't going to equal achieving fuel economy targets that are advertised.

RE: According to whom?
By Brandon Hill on 10/16/2013 10:11:52 AM , Rating: 2
The part you quoted links to a Consumer Reports article (they're also the ones the called out Ford on the optimistic C-Max Hybrid fuel economy numbers before they were revised).

In the real world, I have the feeling that many people are probably applying a bit too much "go" to get these smaller four-bangers moving and therefore hitting the boost more.

And I also have to question the move to these smaller, turbo engines as opposed to larger, normally aspirated models. The 1.6 in the Fusion doesn't even manage to get better power or fuel economy than the larger NA fours in the Altima and Mazda6.

RE: According to whom?
By Pneumothorax on 10/16/2013 10:15:57 AM , Rating: 2
Not only do I agree on questioning the transition to these tiny turbos, but a larger displacement NA engine is going to be much more reliable in the long run as it won't have the typical issues of these small turbos such as intake carbon build up and turbo failures.

RE: According to whom?
By Brandon Hill on 10/16/2013 10:24:12 AM , Rating: 3
Yup. The Honda Civic HF gets the same combined fuel economy as Fit's old Cruze Eco, and does it without turbocharging or direct injection.

When it comes to powertrains, I put a lot of stock in GM's engines... However, a turbo Cruze vs a NA Civic is a no-brainer as far as engine reliability/running costs over the life of the vehicle.

RE: According to whom?
By Spuke on 10/16/2013 12:18:35 PM , Rating: 2
I'm driving a 2007 Pontiac Solstice GXP with a 2.0L turbo DI engine. 19/28 are the EPA figures and I get 28 mpg (last few weeks getting 29). Too much boost will lower your fuel economy. If I keep my boost at 5 psi or lower I get 33 mpg but that's no fun. I fully believe it's driving style killing mileage not car capability.

RE: According to whom?
By dgingerich on 10/16/2013 12:40:04 PM , Rating: 3
You're right about driving style killing mileage, but also the driving styles of the testers are inflating the numbers. I'd bet the numbers some of these car companies are putting out are done with a driving style that would have people merging onto a highway doing 35-40.

RE: According to whom?
By fic2 on 10/16/2013 1:04:28 PM , Rating: 2
You mean like people around here normally do? Freaking kills me that most people don't know to accelerate on that long strip of asphalt before they hit traffic.

RE: According to whom?
By dgingerich on 10/16/2013 2:04:02 PM , Rating: 2
Yeah, I've lived in 4 different major metro areas, and I've seen that in every one, but a little more pronounced in certain areas of Chicago. (NW suburbs of Chicago are DANGEROUS. you have a mix of super aggressive, from downtown, and super passive people, from the local area. Getting caught between them is a really bad idea.) Stupid is everywhere.

I recently saw an old woman in the Denver Tech area in the evening rush hour merge onto I-25 doing about 40, and move over two lanes at once. It caused a 7 car accident across those two lanes from the people who had to slam on their brakes to avoid her, and she didn't even seem to notice the chaos and damage she unleashed. Luckily, I was in the third lane over and missed it all, and managed to pass her. She didn't even signal in any of her lane changes and moved all the way over to the left lane, doing 55 in a 65 zone, causing all sorts of traffic problems behind her, all in the less than 3 miles I watched her until I got off the highway.

A lot of the people I talk to who drive that way think it's safer, clueless of what they unleash on other people. I've tried explaining it, and they just come back with "those other people shouldn't be going that fast anyway." It's the Dunning-Kruger effect in its full glory.

RE: According to whom?
By Philippine Mango on 10/17/2013 6:40:51 PM , Rating: 2
Your story about the old woman driving reminded me of this video:

RE: According to whom?
By Jeffk464 on 10/16/2013 5:18:20 PM , Rating: 2
No you accelerate faster when you need to like getting on the freeway and mellow out when its not necessary. Watch most people on the freeway, when a car moves out of the lane in front of them they gun it immediately to fill in the gap.

RE: According to whom?
By Mint on 10/16/2013 4:20:00 PM , Rating: 2
Slow acceleration doesn't help efficiency much.

If you ever look at an engine's BSFC chart, they're most efficient at ~80% throttle (low RPM, of course). Even for small engines, there's enough power there to avoid "merging onto a highway doing 35-40".

The biggest style factors on efficiency is speed (due to air resistance) and number of acceleration-deceleration cycles (especially with non-hybrids). The latter usually goes up with lead-foots, tailgaters, and pathological lane-changers even when they obey speed limits.

The other factor, of course, is your route. Lots of stop signs make your fuel efficiency tank. The EPA city test is representative for a lot of people, but not everyone. I only average 10-15 mph when off the highway due to traffic, stop signs, and lights.

RE: According to whom?
By Reclaimer77 on 10/17/2013 4:19:07 PM , Rating: 2
One thing I hate about new drive-by-wire throttle systems is that it's almost impossible to gauge your throttle position, due to electronic trickery. You might only be using 30% of the pedal, but the engine is electronically advanced to 60%. Think you're only using 50% throttle under acceleration? Wrong, you're using like 80%!

I get why they do it, it makes the car feel faster and quicker at all times, because it's always using more throttle than your foot is applying.

RE: According to whom?
By superstition on 10/19/2013 12:51:44 AM , Rating: 2
Is this true for current diesel cars? My Passat TDI 6 speed "automated manual" (in automated mode) seems to get much better mileage (according to the computer) when I accelerate leisurely.

RE: According to whom?
By BikeDude on 10/17/2013 5:51:16 AM , Rating: 2
Make sure you compare apples to apples.

If you choose a V6 NA over an inline 4-cylinder turbocharged engine, you might get the same performance, but...

Make sure the larger engine is still maintainable. A colleague of mine was charged an excessive amount of money to replace a simple thermostat on his VW Passat (w/V6). It is so difficult to gain access to the thermostat so what should be a simple procedure becomes a very complex operation. Unless you enjoy doing such jobs yourself, you might not be saving the kind of money you think you are.

I've replaced the thermostat on my Saab 9000 2.3T myself. It is a much faster car than my colleague's VW and the thermostat was easily replaced.

The turbo isn't that hard to replace either. I got my dad a second hand low-mileage turbo for $200. Still less than what my colleague paid for that thermostat.

As for fuel economy: Yes, the faster you get up to speed, the sooner you run the risk of having to slow down. Every press of the boring brake pedal means a loss of energy, so faster will always be more expensive. However: I have the choice every time I ride my car. And I can accelerate out of potentially dangerous situations.

RE: According to whom?
By hpglow on 10/16/2013 11:55:51 AM , Rating: 2
My 2000 VW Jetta TDI just flipped 200k miles a month agao. That is with it pushing 24lbs boost up over the stock 17lbs for the last 100k miles. A well designed turbo engine is just as reliable if not over-built compared to its NA counterpart. The last GM car I bought seized after 140k miles. All my vehicles get their proper maintenance. Modern turbos aren't like the turbos of the past they are far more durable.

RE: According to whom?
By bobsmith1492 on 10/16/2013 12:18:32 PM , Rating: 2
And the turbo in my brother's 04 Jetta TDI died with around 100K miles just after he bought it. Point is a sample size of 1 is not very informative.

RE: According to whom?
By Devilboy1313 on 10/16/2013 3:35:41 PM , Rating: 2
If it died just after he bought it I see the problem. The last owner knew there was something wrong and wanted to pass on the problem to somebody who may not have taken it to a professional to be checked.

Min sample size should always be a diverse 50+.

RE: According to whom?
By Jeffk464 on 10/16/2013 5:21:22 PM , Rating: 2
its a bummer and expensive to fix on an old car. You can always open up the turbo and take out all the insides and put it back in. The car will run fine you just loose a lot of power.

RE: According to whom?
By Heidfirst on 10/16/2013 5:15:34 PM , Rating: 2
except that your 2000 VW isn't a modern turbodiesel ...
Modern turbodiesels have very high pressure common rail injection, DPFs, DMFs etc.. They may be more durable but they are less reliable because they are more complicated.;) & when the common failures occur in the UK you are typically looking at $1500 fixes.

RE: According to whom?
By superstition on 10/19/2013 12:54:41 AM , Rating: 2
That's nothing compared to the timing chain replacement with gears cost for the B5 Passat or the fuel system failure problem due to metal shards with the more recent CR VW diesels.

Bosch and the EMA in general warned, at least as early as 2008, that the lubricity of US diesel will cause premature wear. Their designs were not made for anything about 460.

RE: According to whom?
By FITCamaro on 10/16/2013 10:26:54 AM , Rating: 2
I have a 2013 Altima SV now and yes the fuel economy is quite good. I average 38 on the freeway as advertised and average around 35 in my daily commute.

I really like the way the fusion looks but yeah the fuel economy wasn't as good. I think that's because of weight though.

The Altima is 3182-3230 lbs for the 2.5L models.
The Fusion is around 3615 lbs. They don't have individual curb weights listed for particular models.

RE: According to whom?
By Brandon Hill on 10/16/2013 10:31:33 AM , Rating: 2
I hope I'm not getting you mixed up with Reclaimer (I think that he's the Subaru nut), but you seem to have gone through a lot of cars in the past few years ;)

IIRC, you've had a Cobalt SS, a GTO, the Cruze, and now an Altima in the span of maybe 3 or 4 years?

RE: According to whom?
By Monkey's Uncle on 10/16/2013 11:18:55 AM , Rating: 2
Perhaps he works in a car dealer?

RE: According to whom?
By SilthDraeth on 10/16/2013 11:33:24 AM , Rating: 2
"In a car dealer"


RE: According to whom?
By syslog2000 on 10/16/2013 11:54:49 AM , Rating: 2
Lol! Busted! Fitcamaro, you better have a good excuse ;)

RE: According to whom?
By Brandon Hill on 10/16/2013 12:02:57 PM , Rating: 2
I wasn't trying to "bust" him. As a car guy, I just notice things like that when they are mentioned.

RE: According to whom?
By FITCamaro on 10/16/2013 1:33:40 PM , Rating: 2
In 8 years I've had 4 cars:

2005-2008 Cobalt SS 2.4L 5M
2008-2012 GTO 6M
2012-2013 Cruze Eco 6M
2013 Altima

Cruze was only replaced because of a semi backing into it.

RE: According to whom?
By Brandon Hill on 10/16/2013 1:39:55 PM , Rating: 2
OK, I got ya. I caught on at the tail end of your Cobalt days and then the mishap with the semi skewed things a bit.

Sorry to hear about your Cruze though :(

RE: According to whom?
By FITCamaro on 10/16/2013 2:52:12 PM , Rating: 2
I've been on this site since 2002 I think when I had an 87 IROC. Then was an 89 Camaro RS/Z28 clone with nothing stock.

RE: According to whom?
By Jeffk464 on 10/16/2013 5:24:25 PM , Rating: 2
replaced because of a semi backing into it

Yeah, thats pretty easy to do.

RE: According to whom?
By Reclaimer77 on 10/16/2013 1:44:57 PM , Rating: 2
Sorry Brandon I can barely hear you out here, bad signal. I'm still in line at the dealership personally reserving my spot for the first BRZ STI in my area!!

If you see my girlfriend, tell her I love her, and there's a spot for her in my tent. Also I'm pretty hungry...

RE: According to whom?
By Brandon Hill on 10/16/2013 1:49:03 PM , Rating: 2
You're hungry? I'll get you a full plate of torque. You're gonna need it ;)

Seriously though, congrats!

RE: According to whom?
By Spuke on 10/16/2013 7:52:09 PM , Rating: 2
BRZ STI??? I needs to do some internets searching!

RE: According to whom?
By Brandon Hill on 10/16/2013 10:10:14 PM , Rating: 2
It's not what you think though (no turbo); it's more of a handling package AFAIK:

RE: According to whom?
By Reclaimer77 on 10/17/2013 1:39:26 AM , Rating: 2
Nope. It's already been confirmed. Big power increases.

Come on, you actually believed something would be badged "STI" and NOT be boosted? Tisk tisk :P

RE: According to whom?
By Spuke on 10/17/2013 3:51:12 PM , Rating: 2
I don't know Rec. Seems to be quite a bit of confusion on the BRZ STi still. Can't seem to get a straight answer anywhere. Guess it's just a wait and see. Even if it does exist, I need to see lap times. Tired of buying overly compromised "sports" cars.

RE: According to whom?
By cruisin3style on 10/16/2013 8:12:13 PM , Rating: 3
FIT is right, people rating him down just don't know how to drive other than: "if i'm not on the g0dd4mn brake, i'm on the f#@king gas b!tch!"

it is because most people drive automatics, and may never have touched a stick in their life. you can decelerate by letting off the gas! you don't have to speed up until you have to brake!

one thing i see all the time that is a total waste of gas is people accelerating towards a red light, and none of the lanes are empty (in case the red light turns green before they get to it and they can then just cruise through). People even pass me when i'm engine braking toward a red light, even though the red light is coming up very soon, and like i said there is nowhere to go.

i picked up a used mazdaspeed3 recently that is rated something like 18 city/25 highway but 25 is the worst i've gotten and low 30s is the highest. and i do plenty of city driving, at least 1/3 of my driving is city, and i do not drive like an old lady.

you just have to know how not to drive like a cock.

RE: According to whom?
By Spuke on 10/17/2013 3:58:57 PM , Rating: 2
one thing i see all the time that is a total waste of gas is people accelerating towards a red light
I thought I was the only one that noticed that. I see this crap ALL of the time. And what's up with the continuous acceleration between two points? There's a long stretch of road on my commute that starts at a stop sign and goes past a freeway entrance (about 6 miles). Most people turn onto the freeway. At LEAST 90% of the people I follow on this stretch accelerate the ENTIRE section, hitting their fastest speed on the last 1/3, then slow for the onramp. WTF is that?! No wonder most people can't match EPA mpg ratings.

RE: According to whom?
By Philippine Mango on 10/17/2013 6:49:33 PM , Rating: 2
Yeah I drive a 2007 ES350 and I average 26-28mpg with 50-50 city highway driving but then again I'm pretty light on the throttle and I try to get into the highest gear as quickly as possible and maintain speeds that keep the car in a higher gear with the torque converter locked up.

RE: According to whom?
By Samus on 10/16/2013 9:34:42 PM , Rating: 2
There is definitely a particular way to drive a turbo engine, just like there is a diesel.

Anybody jumping in a turbo I4 and driving it like a V8 is going to be disappointed in a lot of ways other than poor fuel economy. Boost = efficiency. Boost is attained at higher RPM's. You can't just keep the machine bogged down driving in the city, you need to have some fun with it which will actually result in improved MPG.

RE: According to whom?
By Reclaimer77 on 10/16/2013 9:48:33 PM , Rating: 2
you need to have some fun with it which will actually result in improved MPG.

LOL that hasn't been my experience with turbo 4's :)

However I concede that my car isn't tuned for economy. Just the way I like it.

RE: According to whom?
By superflex on 10/16/2013 1:32:40 PM , Rating: 1
Nothing says chick magnet like a Chevy Cruze Eco.
"Hop on in baby, and well hit the Taco bell drive thru. Feel free to get anything from the value menu".

RE: According to whom?
By FITCamaro on 10/16/2013 1:35:09 PM , Rating: 5
Uh...if you drive a car to pick up women, you have other problems. My fiance didn't give a crap about what kind of car I had. Just as long as I had a good job, reliable transportation, and treated her right.

RE: According to whom?
By FITCamaro on 10/16/2013 1:38:02 PM , Rating: 1
Let me add that I drove my GTO because it was fun. And most chicks didn't like it either because it was loud. If I wanted to impress chicks with a car I'd buy a BMW like most other douchebags out there.

RE: According to whom?
By Jeffk464 on 10/16/2013 5:27:03 PM , Rating: 2
Beemers are fun to so why are they more douche than the GTO?

RE: According to whom?
By Jeffk464 on 10/16/2013 5:08:55 PM , Rating: 2
Neither drop the weight of the car so it moves well on a typical 4cyl like in the accord.

Low-power operation
By Dorkyman on 10/16/2013 12:29:03 PM , Rating: 2
It's my understanding that where any ICE falls way down in efficiency is in the region of low-power output. One way to reduce that part of the operating region is to use a smaller displacement and then use turbo boost to match the maximum output of the non-turbo engine.

Another way is to shut down one or multiple cylinders. Aside from the parasitic friction of the non-functioning cylinders, this too would be a way of significantly increasing efficiency at low power.

There was a disastrous Cadillac engine project many years ago that apparently didn't turn out well, but there are contemporary engine designs that do this. Any feedback about this? It would seem to me that a modern, high-tech, digitally-controlled cylinder shutdown would be far preferable to the turbo alternative.

RE: Low-power operation
By Mint on 10/16/2013 4:06:34 PM , Rating: 2
A big source of low power efficiency loss is pumping loss. Because the intake operates near stoichometric air-fuel mixtures, the only way to reduce output is by lowering the total molecules of this mixture entering the cylinder. Traditionally, this is done by a throttle valve, which literally restricts the intake, thus wasting energy as air/fuel squeezes by.

The Atkinson engine tries to reduce pumping losses by letting air/fuel flow freely into the cylinder, but then let some of it flow back out before shutting the valve and compressing. That free flow is the difference between a regular cycle with reduced throttle and an Atkinson cycle with an equal rate of fuel consumption.

Cylinder shut-down would achieve a similar goal: while they still have friction, there's no air/gas flowing in and out. It may not be as effective as Atkinson, though, because compressing and expanding gas in a closed cylinder will have some losses.

Small displacement turbos go after frictional losses instead of pumping losses. I don't have any data to say which approach is better, but it's nice to see progress on both fronts.

RE: Low-power operation
By snhoj on 10/16/2013 7:34:05 PM , Rating: 2
I believe that most of the benefit of the Atkinson cycle engine is an improvement in the thermal efficiency of the engine. The Otto cycle engine sucks a volume of air into the cylinder compresses it and heats it by burning fuel in it to increase the pressure in the cylinder (heat plus combustion products) it then expands the gasses to the same volume as prior to compression before exhausting the gasses. This means that the still heated gasses are going to be exhausted while considerable pressure energy remains meaning that pressure energy is no longer able to do useful work in the engine. That remaining energy is effectively dumped via the exhaust system. A true Atkinson cycle engine has a shorter compression stroke than power stroke and so extracts more of the pressure energy available before exhausting the gasses. This would improve the thermal efficiency of the engine (more of the heat from burning of fuel is converted to work) while at the same time reducing its power density.

While the engine would probably spend more time with its throttle further open due to its reduced power density if the engine was built with a larger displacement to compensate, that would have the effect of normalizing the throttle position and pumping losses would be greater due to induction air passing into and out of the cylinder on the intake side. Pumping air into the cylinder past the intake valve and then pushing some of it back out again past the intake valve. This would be an extra double pass of the intake valve for gasses that are back flowed out of the cylinder on the intake side with a small pressure drop or energy loss for each pass. A larger displacement could allow larger intake and exhaust valves for an easier breathing engine. It would also mean bigger pistons and heavier crankshaft and consequently bearing surfaces with a larger area and increase sliding velocities for greater frictional losses. Also the increased engine weight would negatively affect the vehicles overall efficiency.

RE: Low-power operation
By Mint on 10/17/2013 6:58:57 AM , Rating: 2
A shorter compression stroke does the exact same thing as putting less air-fuel mixture into the cylinder. You get the same number of molecules of air/fuel in there compressed to the same volume and expanded to the same volume after ignition.

The big difference is that Atkinson does that more efficiently. Air doing double passes though open valves isn't nearly as bad as air going across a throttle that is more closed. The pressure drop is clearly far less with the former than the latter.

You're right that there are negatives with a larger engine, but it's a matter of magnitudes to see whether they are worth it.

RE: Low-power operation
By Strunf on 10/17/2013 9:44:00 AM , Rating: 2
VW has some engines that can shut down 1 or 2 cylinders under low load, it's called ACT. I think some models have this and the Turbo.

RE: Low-power operation
By Reclaimer77 on 10/18/2013 7:59:59 PM , Rating: 2
VW's best feature is called TCS, for T otal C ylinder S hutdown.

Toyota is right
By chillingrsx on 10/16/2013 11:31:50 AM , Rating: 2
From my knowledge. Honda was the first to go smaller engine for turbo when they came out with the RDX back in early 2000. So guess what, in 2013, they switch to a V6 and I'm loving everything about it. I currently own one. During the test drive, I test drove both model, the turbo and the naturally aspirated V6. It's much smoother and linear. I believe N/a is the way to go, less maintenance and better gas mileage. What they should focus on is reducing the weight. I believe any turbo engine will not have the same reliability as a n/a engine.

RE: Toyota is right
By DT_Reader on 10/16/2013 4:46:23 PM , Rating: 2
Honda was not first. Volvo did this decades ago. Their turbo 4 had more horsepower and better mileage than their 6.

The number one factor in gas mileage is vehicle weight. If a turbo 4 weighs less than the equivalent 6, the vehicle will get better gas mileage.

Why doesn't anyone make a diesel hybrid? Maybe they do in Europe, but why not here? Why isn't the Chevy Volt a diesel? Makes no sense to me. The five to ten cent/gallon cost premium is more than offset by the increased efficiency.

RE: Toyota is right
By twhittet on 10/16/2013 6:23:20 PM , Rating: 2
You mean 50 cent diesel premium over regular gas?

RE: Toyota is right
By silverblue on 10/18/2013 9:04:13 AM , Rating: 2
PSA do in Europe, along with Volvo, Mercedes and VW:

RE: Toyota is right
By inperfectdarkness on 10/18/2013 4:13:06 AM , Rating: 2

Toyota has had several small, boosted engines. The MR2 comes to mind. They are trying to BS people into believing that LIFETIME operating costs of hybrids are lower than a comperable turbocharged engine. Again, BS. Lithium batteries don't come cheap.

As far as reliability? Turbos have come a LONG, LONG way since the 80's. Materials have vastly improved. Ford's Eco-Boost v6 has made a believer out of millions--and there's a reason for that. Yes, N/A's will have a more linear power-curve. That said, to deliver any given amount of power, you can almost always do it with less weight on a smaller, boosted engine--than you can on a larger, naturally aspirated engine.

I'll swear by turbos. They deliver an altogether more enjoyable driving experince. It's no less visceral than that of the individuals who swear by manuals over automatics.

Pretty sure Mazda beat them to the punch
By yottabit on 10/16/2013 1:46:12 PM , Rating: 2
A more relevant example than the Mazda Millenia motor (which were supercharged) would by the Skyactiv 2.0 / 2.5 L

IIRC those run in a partial/modified Atkinson cycle under light load conditions, accomplished through the variable valve timing

Hence a 2.5L that can get ~38+ MPG Hwy

RE: Pretty sure Mazda beat them to the punch
By FITCamaro on 10/16/2013 2:51:08 PM , Rating: 2
Don't think the 2.5L in the Altima is Atkinson cycle and it gets 38 mpg highway...

By twhittet on 10/16/2013 6:30:22 PM , Rating: 2
Though it does have CVT....

It's All About Torque
By Stiggalicious on 10/16/2013 10:51:28 AM , Rating: 2
After switching from a naturally-aspirated to a turbo engine, I will never buy a car with a naturally-aspirated engine ever again. Turbocharged engines that are designed well (like Ford's 2.0T in the Focus ST or the VW/Audi 2.0T) have oodles of low-end torque and almost no turbo lag whatsoever. They turn the cars they're put in into highway overtaking monsters. They last just as long as any normal NA engine* and weigh less. I would much rather have a 1.0T that delivers the same power (and probably more low-end torque) as a 2.5 Atkinson cycle engine. It may sacrifice 1 or 2 MPG, but it makes up for it by reducing the weight and size of the engine significantly (enabling better handling, acceleration, braking, and lower rolling resistance from the tires).

*About the lasting-longer part: If you drive 3-4 miles per day for your commute and don't get your engine and oil up to temp, then yes a turbocharged engine will die sooner. However, nowadays the engine will still outlast the rest of the car since the car tends to wear out and break pretty much everything else by the time 250,000 miles/15 years comes around. Sure, a Crown Vic NA V8 can last for 600k miles no problem, but nearly everyone gets rid of their car by the quarter-million-mile mark.

RE: It's All About Torque
By chromal on 10/16/2013 4:56:44 PM , Rating: 2
I feel the same way, plus I live in Colorado and drive between 5500ft and 12000ft elevation. Did you known that naturally aspirated engines lose 3% of their max horsepower for every 1000ft above sea level that they're driven? This starts to matter when you live at 8700ft and need to literally climb mountains. Turbocharged engines make for a happy engine in Colorado.

By Estee on 10/17/2013 1:37:24 AM , Rating: 2
This DT post seems to make it as if Toyco is resident to turbos. They are not:

"And while Toyota is joining the fight -- Lexus recently trademarked "NX 2.0T" for a two-liter turbo version of its upcoming Lexus compact crossover -- Saga is not convinced that Toyota will emphasize turbocharging across many product lines."

The NX200t aka the hi lux RAV4 Lex will be coming here with that engine. Expect it to proliferate throughout Toyco's portfolio through the coming decade.

By Richard875yh5 on 10/17/2013 4:21:51 PM , Rating: 2
GM is also not really in a hurry going to small turbo engines. The new GM trucks don't use them and yet GM V8 truck gets better gas mileage than the Ford's V6 Ecoboost. They should get this engine Ecoboast instead of Ecoboost, because Ford brags so much about it. LOL

Turbo vs. Atkinson cycle
By JCBlair on 10/18/2013 7:50:55 PM , Rating: 2
I owned a 2002 Saab 9-5, a fairly large sedan that routinely got 31-32 MPG on the highway and cross-country. I live in Colorado and a turbo is the way to go at higher elevations.

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Walmart may get "Robot Shopping Carts?"
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