SkyActiv-X Review, glimpse of possibly what to expect in future CX-5s

The skeptics who doubted that the Mazda version of HCCI would never work have been quiet on this thread so far..... you know, the ones who always predict the worse case scenarios. TNT's I call 'em.

When Mazda announced it a while ago, I thought to myself that they must already have test mules running around with that engine design under the hood, doing testing and ironing out bugs.

The fact that they have now let the press loose on them means they must be supremely confident of the path towards full production models.

And they also see a future for a Gen2 D engine as well, they must be confident of figures for it that keep it competitive with the new X petrol engine.

Good stuff, Mazda!!
 
X-gen Mazda engines due 2019

"Another plus for potential Aussie buyers is that, unlike some engine tech, SKYACTIV-X is not reliant on high-quality fuel to meet performance targets. Indeed, lower octane fuels can be an advantage, Mazda’s experts opined."
 
Certainly a great breakthrough for the ICE. A 2.5L engine with the same application should deliver even more in terms of power and torque.

Motor Authority's fuel consumption test:
The results are encouraging: on a drive route that included a short stretch of unlimited-speed autobahn, meaning speeds of roughly 100 mph, the prototype 2020 Mazda 3 delivered 34.6 mpg and 39.9 mpg in manual and automatic versions, respectively.

Autoexpress:
We’ll have to rely on simulations to gauge improvements in fuel economy though. According to Mazda, over our 50km run in an automatic SKYACTIV-X equipped mule, including urban, rural and autobahn driving we managed 42.2mpg. According to Mazda, a similar SKYACTIV-G equipped Mazda 3 would have returned 36.2mpg if driven down the same route identically, representing a predicted 13 per cent improvement in fuel economy.

Driving CA:
Now as impressive as those numbers are it was the ones generated in the automatic model that underscore the real potential. Again, I recorded 6.5 L/100 km overall and 6.7 L/100 km in the city/rural portion of the drive in the current Mazda3. Driving the Skyactiv-X automatic produced economy numbers of 5.4 L/100 km overall and a city/rural number of 5.5 L/100 km — that’s an improvement of 17.2 per cent and 17.8 per cent, respectively.
 
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I think its funny that they label the vertical axis with torque, and units (always appreciated) but have no numbers there.

The comparison is to highlight the different torque curves when using different octane fuels. It's not a comparison table of torque numbers and besides, the Skyactiv-X is still in prototype form and they can't reveal the real production torque figures yet. You can clearly see it is much better than the Skyactiv-G. If you really wanted to, you can try and measure the scales and work out the difference between the two with the current Skyactiv-G data.
 
More information:

Mazda SkyActiv-X could save you over $400 per year by preferring Regular petrol over Premium

Note the comment about 2.5L Turbo:

"The announcement of SkyActiv-X tech comes barely a year after Mazda's return to turbocharged petrol technology with the CX-9's 2.5-litre engine, but Hitomi-san assures the brand isn't necessarily moving away from the turbo. Instead, he can see turbos being the solution for high performance models in the future. When asked if this could include the upcoming rotary-engined vehicle, Hitomi responded "of course." Watch that space."
 
I think that Toyota 2.5 hybrid and the next generation MZD Connect might roll out in 2019 according to this,

IMG_0433.jpg
 
The comparison is to highlight the different torque curves when using different octane fuels. It's not a comparison table of torque numbers and besides, the Skyactiv-X is still in prototype form and they can't reveal the real production torque figures yet. You can clearly see it is much better than the Skyactiv-G. If you really wanted to, you can try and measure the scales and work out the difference between the two with the current Skyactiv-G data.

Well, it doesn't make a lot of sense. It shows a major increase in torque and horsepower going from 91 RON to 95 RON with the current SkyActiv-G, which is not real world. And it shows SkyActiv-X making significantly more torque at lower RPM when using the lower octane fuel, which is really odd for a high compression engine, but then at high RPM it's the reverse. I'd love to see an explanation for that. For now I'm assuming this is just marketing bulls***.
 
Call it what you will. When they are good and ready the figures will be revealed

I'm not saying they owe us numbers. Its the graph, a pet peeve of mine as an engineer. Don't list units if you aren't going to provide values. If its intended as qualitative only, just label the axis "Torque". Obvious they have a model with real values or they wouldn't be able to say x% more, let alone draw a proportional curve next to the others.

In any case, it should be a simple matter to overlay a scale based on one of the two existing engines.
 
I'm not saying they owe us numbers. Its the graph, a pet peeve of mine as an engineer. Don't list units if you aren't going to provide values. If its intended as qualitative only, just label the axis "Torque". Obvious they have a model with real values or they wouldn't be able to say x% more, let alone draw a proportional curve next to the others.

In any case, it should be a simple matter to overlay a scale based on one of the two existing engines.
I understand where you're coming from but in their case my guess is that it aren't putting the figures you because at this moment they probably aren't reaching their targets. When they have they will
 
I understand where you're coming from but in their case my guess is that it aren't putting the figures you because at this moment they probably aren't reaching their targets. When they have they will

I won't press the point, since I don't have the context for those graphs. They are snipped out of something.

This is similar to when I objected to a poster using lbs as unit of torque. Perhaps its semantics, or me just being pedantic.

If you show me a graph with shaped lines and an X (horizontal) axis with scale (numerical values), I expect to be able to interpolate values from the Y-axis, especially when the Y(vertical) axis is labeled with units of measure. In this case, NM. If they hadn't put a scale on the X axis, I also wouldn't have said anything. That's what I'd expect if they were just trying to show the general relationship between the 3 engines.

This looks like a chart that was generated with data points, not a powerpoint freehand drawing for marketing managers.

Again, I'm not saying they owe us the data, or should have shown the data, just don't give us a format for data without the data. In other words, if you aren't giving the data, don't pretend to. It reinforces scientific illiteracy.
 
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I won't press the point, since I don't have the context for those graphs. They are snipped out of something.

This is similar to when I objected to using a poster using lbs as unit of torque. Perhaps its semantics, or me just being pedantic.

If you show me a graph with shaped lines and an X (horizontal) axis with scale (numerical values), I expect to be able to interpolate values from the Y-axis, especially when the Y(vertical) axis is labeled with units of measure. In this case, NM. If they hadn't put a scale on the X axis, I also wouldn't have said anything. That's what I'd expect if they were just trying to show the general relationship between the 3 engines.

This looks like a chart that was generated with data points, not a powerpoint freehand drawing for marketing managers.

Again, I'm not saying they owe us the data, or should have shown the data, just don't give us a format for data without the data. In other words, if you aren't giving the data, don't pretend to. It reinforces scientific illiteracy.

People are demanding more info since Mazda made HCCI known. They should provide proper data - I agree with you but we are only hypothosising why they aren't. They had to publish something to appease the curiosity until they get it all sorted
 
Starting from 2019, Mazda will offer the mild-hybrid versions of its vehicles. The automakers first all-electric vehicle is also set to be launched in 2019 which will also have a rotary range extender option. The EV will be showcased in 2018.
In 2021, Mazda will introduce the plug-in hybrid vehicles. Mazda's Managing Executive Officer for powertrain development, Ichiro Hirose states that the decision to make an EV before a plug-in hybrid makes more sense with the regulations in key markets.

Read more at: https://www.drivespark.com/four-whe...-portfolio/articlecontent-pf74786-023632.html
 
Starting from 2019, Mazda will offer the mild-hybrid versions of its vehicles. The automakers first all-electric vehicle is also set to be launched in 2019 which will also have a rotary range extender option. The EV will be showcased in 2018.
In 2021, Mazda will introduce the plug-in hybrid vehicles. Mazda's Managing Executive Officer for powertrain development, Ichiro Hirose states that the decision to make an EV before a plug-in hybrid makes more sense with the regulations in key markets.

Read more at: https://www.drivespark.com/four-whe...-portfolio/articlecontent-pf74786-023632.html

Toyota input here
 
You know I was thinking about the different curves for the different octanes and there may be a simple explanation. There are 2 versions of the current SkyActiv G motor. One has a compression ration of 13:1 which is sold in the US and Australia and runs on 91 RON (87 octane). The other has a compression ratio of 14:1 which is sold in Europe and runs on 95 RON (91 octane). The one with the higher compression ratio does in fact produce a bit more power and torque. I suspect we may simply be seeing that they'll do the same thing with SkyActive X as they don't want to have to require premium in the US or Australia and I'm sure there are some other countries getting the lower octane version as well due to the fuel standards there.

So they're not showing two graphs of the same engine on different types but rather the two versions of the engine designed for two different fuel types respectively.
 
You know I was thinking about the different curves for the different octanes and there may be a simple explanation. There are 2 versions of the current SkyActiv G motor. One has a compression ration of 13:1 which is sold in the US and Australia and runs on 91 RON (87 octane). The other has a compression ratio of 14:1 which is sold in Europe and runs on 95 RON (91 octane). The one with the higher compression ratio does in fact produce a bit more power and torque. I suspect we may simply be seeing that they'll do the same thing with SkyActive X as they don't want to have to require premium in the US or Australia and I'm sure there are some other countries getting the lower octane version as well due to the fuel standards there.

So they're not showing two graphs of the same engine on different types but rather the two versions of the engine designed for two different fuel types respectively.

hmm you think I can purchase a Euro ECU from ebay or something and put into a North American CX-5 and take advantage of 91+ octane to get extra HP?
 
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