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SKYACTIV-X: first commercial gasoline engine to use compression ignition

www2.mazda.com

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Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#151

Post by dsfyu404ed »

NickM wrote: post #117
spitfire wrote: post #103

Earlier quoted context omitted.

I believe it's a "luxury/enthusiast" strategy. I believe the auto market will play out something like the watch market did with the introduction of the quartz watch. Most people just want to tell the time, so they buy a quartZ. Similarly most people just want to get from A to B, so will buy an electric (automated) car. Some people enjoy the mechanics of the thing. So they buy a nice mechanical watch. These watches we…

Perhaps, but I wonder if we won't see more countries go the way of Norway/France/Britain and ban gasoline cars altogether once electric vehicles become more competitive and mainstream....

The less popular ICE vehicles are the less of an environmental problem they are and the less will there is to ban them.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#152

Post by pkulak »

borski wrote: post #7
Danihan wrote: post #3

>Compression ignition and a supercharger fitted to improve fuel economy together deliver unprecedented engine response and increase torque 10-30 percent over the current SKYACTIV-G gasoline engine.*3 Wow. I already have a 2016 Mazda 3 that gets around 40MPG (even though it's not a hybrid) and it's already pretty peppy. Probably the best car I've owned, and I've owned several nice sports sedans. Getting 40MPG is too c…

OK, so honest question: I have a 2012 Mazda 3 which, presumably, gets 40mpg. But I can't realistically get anything above 29mpg on average. Am I just an aggressive driver? :) [edit] I agree, by the way, that the cars are incredibly fun to drive, for being "fuel efficient."

If you don't spend 95% of your time on a freeway, you'll never get close to the top MPG. This is how people like to compare their cars to hybrids: their car's highway MPG to a hybrid car's combined. Problem is, the hybrid probably doubles the their MPG in the city. But, if you're a long-range commuter, I guess that doesn't matter much.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#153

Post by dsfyu404ed »

usrusr wrote: post #138
borski wrote: post #7

Earlier quoted context omitted.

OK, so honest question: I have a 2012 Mazda 3 which, presumably, gets 40mpg. But I can't realistically get anything above 29mpg on average. Am I just an aggressive driver? :) [edit] I agree, by the way, that the cars are incredibly fun to drive, for being "fuel efficient."

The correlation between efficient driving and aggressive driving is far from perfect. The "pulse and glide" method from the wikipedia page linked in a sibling comment would seem quite aggressive for example and on the other end of the scale, I have often seen "moving roadblocks" running their engine at RPM far too high for efficient cruising (e.g. when people drive a manual who are afraid of shifting).

Hauling ass from one light to barely run a red on the next one is a hell of a lot more efficient than seeing the yellow, accelerating like an old man, coasting for awhile, braking to a stop and idling for several minutes.

Every time you touch your brakes you're throwing away the energy it took to get to that speed. Coasting through off ramps at highway speed is good for the environment.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#154

Post by trhway »

jonsen wrote: post #94
ChuckMcM wrote: post #18

A reuters story on how it works: https://www.reuters.com/article/us-mazda-strategy-idUSKBN1AO... So this is 'gasoline' diesel. Or diesel without the NOx. Which, in theory, would give better fuel economy and possibly better torque. And it will ship in cars in the 2019 model year (so possibly as early as late next year). To me, it sounds like a "Don't pass"[1] bet on electric cars. Which they also are working with Toyo…

Someday someone might invent an efficient process for making gasoline from renewable energi sources.

it is called battery charging :). Basically it is making the fuel - Li - out of the ash - lithium oxide. The amount of Li and available for "burning" oxygen in the current batteries is very small and where is no principal reasons it can't be increased 10-fold to something like 10% by weight (especially in the metal-air schemes) at which moment it will leave gasoline engines well behind in all respects.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#155

Post by thenewwazoo »

aidenn0 wrote: post #134
greggyb wrote: post #8

Earlier quoted context omitted.

I can get 40MPG (US) highway with a 2015 Mazda3 and a somewhat aggressive driving style. City is usually low 30s. The manual transmission is also one of the nicest I've ever driven. These are great cars.

I only wish you could get the 2.5L in a manual with no moonroof. That would probably get me to buy a new car. I have an 07 Mazdaspeed3 that is getting long-in-the-tooth, and it gets terrible mileage (19 in town, high 20s on the freeway). The best I can say about the shifter is that you get used to it. I don't think I need quite as much pep as my current car (plus all current hatchbacks that are comparable performance…

For what it's worth, I went from a WRX to a 2L 3i and don't miss the extra horsepower because we felt, frankly, that they're all slow, so why pay a premium for slightly less slow? With that said, it's plenty fast enough for city driving and is the most fun FWD drive car I've driven, bar none. Hell, it's the best car I've owned and only barely not the most fun (after my RX-7). The interior is great, it's cheap to run, ...

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#156

Post by ouid »

pkulak wrote: post #148
ouid wrote: post #140

Earlier quoted context omitted.

I visited a Tesla store once in mountain view, and they have a great little demo where you can check the cost of charging your car in various states. Washington DC, for whatever reason, gets its electricity from a gasoline power plant. In Washington, the Model S gets 28 MPG. This happened a while ago so I could be misremembering, but regardless I don't believe that the environmental value of electric vehicles has bee…

https://en.wikipedia.org/wiki/The_long_tailpipe#Criticism The biggest nail in the coffin of the long tailpipe fallacy is that you can drive an EV farther on the power needed to refine a gallon of gas than you can drive a ICE car on that same gallon. So, even if you built a gasoline engine that had absolutely no emissions, and oil bubbled up into crude lakes right next to every refinery, EVs would still be more effici…

Refining gasoline seems to be ~88% efficient per your source. While this isn't negligible, it hardly changes the argument.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#157

Post by aidenn0 »

thenewwazoo wrote: post #155
aidenn0 wrote: post #134

Earlier quoted context omitted.

I only wish you could get the 2.5L in a manual with no moonroof. That would probably get me to buy a new car. I have an 07 Mazdaspeed3 that is getting long-in-the-tooth, and it gets terrible mileage (19 in town, high 20s on the freeway). The best I can say about the shifter is that you get used to it. I don't think I need quite as much pep as my current car (plus all current hatchbacks that are comparable performance…

For what it's worth, I went from a WRX to a 2L 3i and don't miss the extra horsepower because we felt, frankly, that they're all slow, so why pay a premium for slightly less slow? With that said, it's plenty fast enough for city driving and is the most fun FWD drive car I've driven, bar none. Hell, it's the best car I've owned and only barely not the most fun (after my RX-7). The interior is great, it's cheap to run,…

There are some dangerously short freeway on-ramps where I live, so "slightly-less-slow" can mean a few extra feet between me and a tractor-trailer.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#158

Post by coredog64 »

fnj wrote: post #102
ChuckMcM wrote: post #18

A reuters story on how it works: https://www.reuters.com/article/us-mazda-strategy-idUSKBN1AO... So this is 'gasoline' diesel. Or diesel without the NOx. Which, in theory, would give better fuel economy and possibly better torque. And it will ship in cars in the 2019 model year (so possibly as early as late next year). To me, it sounds like a "Don't pass"[1] bet on electric cars. Which they also are working with Toyo…

> So this is ... diesel without the NOx NOx is not peculiar to diesel engines. Gasoline engines also generate NOx. All internal engines make NOx. As long as you burn fuel + atmospheric air you get NOx. The atmosphere is 78% nitrogen. Some of it gets oxidized.

The catalytic converter helps to manage this in a gasoline engine. Cats are more difficult for diesel, which led to the ammonia fluids that current diesels use to minimize NOx emissions.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#159

Post by jhayward »

fnj wrote: post #107
komali2 wrote: post #55

Earlier quoted context omitted.

Total individual perspective here, but my dad took me on his worksite like 15 years ago to see the big super gorram awesome trucks (seriously those things are HUGE). When I asked about the engines, he said the trucks had massive diesel generators that powered motors, that in turn powered the wheels and hydraulics. So in a way, lots of construction equipment has kind of already been "hybrid."

An electric power transmission is hardly hybrid. You just have two extra conversions in your transmission, mechanical to electric and electric back to mechanical.

The diesel-electric system used in Locomotives and heavy off-road mining trucks are literally examples of series hybrids. You may be objecting to ththe lack of battery storage, which isn't useful in those applications.

Re: SKYACTIV-X: first commercial gasoline engine to use compression ignition

#160

Post by SeanLuke »

33W wrote: post #92
ChuckMcM wrote: post #18

A reuters story on how it works: https://www.reuters.com/article/us-mazda-strategy-idUSKBN1AO... So this is 'gasoline' diesel. Or diesel without the NOx. Which, in theory, would give better fuel economy and possibly better torque. And it will ship in cars in the 2019 model year (so possibly as early as late next year). To me, it sounds like a "Don't pass"[1] bet on electric cars. Which they also are working with Toyo…

They also have an interesting somewhat-hybrid called i-eloop that uses regenerative braking and a capacitor to power auxiliary systems: http://www.mazda.com/en/innovation/technology/env/i-eloop/

I considered i-eloop when it came out for its first generation, in the 2014 Mazda 3. It was estimated to bump my city MPG by 1. And was only available in a very expensive package. I passed.
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