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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

#41

Post by MagnumOpus »

serpix wrote: post #36
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…

That is horrible mileage. I remember averaging that on a 1997 Opel Astra.

Your Astra weighed 1000lbs less, had no air conditioning and probably no air bags and would have probably killed you in a 40mph collision though, innit?

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

#43

Post by clone1018 »

mikestew wrote: post #19
stirkac wrote: post #2

Mazda is one of those companies just don't stop revolutionizing. First they got rotary to be actually usable. Now this.

The rotaries leaked oil and got terrible mileage, and good luck finding someone to work on them. Other than that, they were zippy. "Usable" they might have been if you keep a low bar, but "practical" they were not.

They didn't leak oil did they? They burned oil as part of the strokes right?

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

#44

Post by busterarm »

mikestew wrote: post #19
stirkac wrote: post #2

Mazda is one of those companies just don't stop revolutionizing. First they got rotary to be actually usable. Now this.

The rotaries leaked oil and got terrible mileage, and good luck finding someone to work on them. Other than that, they were zippy. "Usable" they might have been if you keep a low bar, but "practical" they were not.

Huh? My rotary doesn't leak oil. Mileage is an issue but not significantly worse than other sports cars of that era or even today.

I also could probably connect you with a good rotary mechanic (or several) in all 50 states plus Puerto Rico (hell, especially Puerto Rico)

The biggest issue with the FCs isn't the engine, it's the reliability of the electric systems and heat (as a distant second). With the FDs it pretty much the twin turbos. And with early RX-8s (04-early09) it's a lack of proper engine lubrication due to a design flaw.

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

#45

Post by [deleted] »

busterarm wrote: post #44
mikestew wrote: post #19

Earlier quoted context omitted.

The rotaries leaked oil and got terrible mileage, and good luck finding someone to work on them. Other than that, they were zippy. "Usable" they might have been if you keep a low bar, but "practical" they were not.

Huh? My rotary doesn't leak oil. Mileage is an issue but not significantly worse than other sports cars of that era or even today. I also could probably connect you with a good rotary mechanic (or several) in all 50 states plus Puerto Rico (hell, especially Puerto Rico) The biggest issue with the FCs isn't the engine, it's the reliability of the electric systems and heat (as a distant second). With the FDs it pretty…

[deleted]

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

#46

Post by dpark »

MagnumOpus wrote: post #41
serpix wrote: post #36

Earlier quoted context omitted.

That is horrible mileage. I remember averaging that on a 1997 Opel Astra.

Your Astra weighed 1000lbs less, had no air conditioning and probably no air bags and would have probably killed you in a 40mph collision though, innit?

And that mileage was presumably measured using imperial gallons, which are 20% larger than US gallons. And it probably didn't get 40mpg anyway unless it was on the highway 100% of the time.

http://www.carfolio.com/specifications/models/car/?car=26732...

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

#47

Post by _ea1k »

mikestew wrote: post #19
stirkac wrote: post #2

Mazda is one of those companies just don't stop revolutionizing. First they got rotary to be actually usable. Now this.

The rotaries leaked oil and got terrible mileage, and good luck finding someone to work on them. Other than that, they were zippy. "Usable" they might have been if you keep a low bar, but "practical" they were not.

Rotary engines do not "leak oil", they burn oil a modest amount of oil by design. If you think about it, there really wasn't another way to lubricate them.

Practicality was pretty low, though, as you rightly point out.

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

#48

Post by busterarm »

_ea1k wrote: post #47
mikestew wrote: post #19

Earlier quoted context omitted.

The rotaries leaked oil and got terrible mileage, and good luck finding someone to work on them. Other than that, they were zippy. "Usable" they might have been if you keep a low bar, but "practical" they were not.

Rotary engines do not "leak oil", they burn oil a modest amount of oil by design. If you think about it, there really wasn't another way to lubricate them. Practicality was pretty low, though, as you rightly point out.

Excluding the Miata, when are sports cars ever practical?

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

#49

Post by robin_reala »

oatmealsnap wrote: post #35
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…

Gasoline engines aren't going away for a while; even when every self-driving car is electric, there will be a market for people who want gasoline engines. If it gives a bump in fuel economy to the next (last?) generation of gasoline and hybrid vehicles, great! I also wonder if the maintainability of these engines will be the same as with diesel. That would be another big benefit.

Outside of Europe maybe. Inside, well, UK and France have already said no more ICE vehicles to be sold past 2040, and other countries are planning the similar (including India). That’s a big loss of market and consequent economy of scale.

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

#50

Post by cmrdporcupine »

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…

Mazda is only working with Toyota on electric because they have to for compliance reasons in CAFE states. The CEO has quite recently panned EVs and said they will die when subsidies go away[1]. I'm sure they will produce a compliance-only vehicle available only in California and probably only for lease, like Honda has done with the clarity.

[1] http://www.greencarreports.com/news/1111876_mazda-exec-engin...

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