Mazda Appoints New CEO, Prioritises USA - Wonder If Any Immediate Impact On CX-5
- Thread starter Xeler8ing
- Start date
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- Plano, Texas, USA
SkyActiv-X SPCCI is using compression ignition and spark ignition alternatively like a hybrid switching between electrical motor and gasoline engine. See this Driving Mazda's Next Mazda 3 with Its Skyactiv-X Compression-Ignition Gas Engine article from Car and Driver:
Car and Driver said:
Can't access the article as I'm in the UK, "Sorry, this content is not available in your region." Bloody GDPR (General Data Protection Regulation) Yrwei52, please could you copy and paste the article so that us EU mere mortals can read it? - So much for net neutrality...
I use to think that way as well, about paddle shifters in cars with CVT. However the one in the Accord Sport is actually useful if you know how to use it or what it is for. In cars with traditional automatic transmissions or DCTs, the paddle shifters simply allow you to change gear, up or down, pretty simple. In the Accord Sport, the paddle shifters allow you to select a different ratio that will give you more power or allow engine braking. That's the complicated answer, but I found a different, albeit simpler way to look at it. The paddle shifters in the Accord Sport allow you to select a higher RPM limit. Basically in my experience, driving it in D mode, the RPMs seem to be capped at like 4000 RPM even when you go WOT. This was most likely done in the interest of fuel economy. Using the paddle shifters to downshift allows the engine to rev up past 4000 RPM, which means you get more power, because in the 2015 Accord with the 2.4 NA engine, max power is at like 6500 RPM.
So to give an example, I'm approaching a traffic light that's about to turn yellow. If I was in the CX-5 and wanted to beat the light, I would floor it and activate the kick-down switch for maximum downshifts and then zoom along. If I was in the Accord Sport, I would/could maintain my foot's position on the gas pedal and just hit the paddle shifter twice to downshift, which will immediately put me at a higher RPM and give me more horsepower. Also I'm not sure at what RPM it activates in D mode, but at higher RPM, VTEC kicks in and the car roars and actually pushes me back into the seat. If you put it in Sport mode (yes the Accord has Sport mode too), the car will actually go all the way up to redline, which is where the car makes the most power.
The reason why manufacturers are trying to introduce fake shift points into cars with CVT is simply because people think it is unnatural for the car to not shift, even if not shifting and staying in peak power is more efficient than shifting and then having it climb the rev range again. People are just used to engines going up and down the rev range, along with the sound of the engine doing so, that driving a CVT car that is going fast but is stuck at 6500 RPM, makes it a weird driving experience. And it does feel weird when it happens, but only because we are not used to it.
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Read the article posted above. They aren’t using the spark plug in the same way. They ignite small fuel ball which raises the pressure causing the rest of the cylinder to spontaneously combust. That’s why it’s called spark controlled compression ignition not spark ignition.
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They also aren't using the supercharger the same way other engines do as well.
Exactly, this engine is designed for efficiency not performance. And they’re using a lot of existing technology in novel ways.
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- Plano, Texas, USA
We’re getting into semantics here about compression ignition and spark ignition. As in Car and Driver article, they even using the term “switches to conventional spark ignition”, and “behaves so similarly in each ignition state” means two different processing states going on for ignition. So by saying the lower octane on gasoline the better for SkySctiv-X SPCCI earlier is not true because the spark ignition is also involved.
HCCI is good for simplicity and efficiency. Mazda now keeps adding more devices such as ignition system and supercharger making the SkyActiv-X SPCCI very complicated. Not the way I would like to see on SkyActiv-II development several years ago.
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- Plano, Texas, USA
Thanks for making those imagines on the article! (drinks)Here you go
And why you can view it in Australia but Jonno21 cant view it in UK? (uhm)
Good point. Perhaps Skyactiv-X is their new Rotary project to chase. In that case the improvement on the existing skyactiv should be the true skyactiv-2.
You need to read up on it a bit more. Maybe check out the EE video on YouTube where Jason Fenske explains it. It’s not using conventional spark ignition at all. Nor is it using the super charger in the conventional way.
The GDPR legislation is supposed to concentrate the minds of those companies holding your data although see https://gdprhallofshame.com/ Some companies, instead of complying just deny access to their website (e.g. some US newspaper publications). So, the logical conclusion is that the companies denying access must have data about you from cookies etc that is insecure in some way, otherwise what have they got to hide and why can't they comply with the regulations? It's easier for them to just deny access i suppose. (Am I being too cynical?)
Thanks xeler8ing for the mag site extractNo thanks button on this site (there should be one)
No worries
