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Goran Dzepina, look this:
MAZDA'S AKIRA MARUMOTO:
"The engine really achieves good performance through high-octane gasoline. We were considering just using regular gasoline. But we decided to recommend high-octane premium gasoline for the Skyactiv-X. The biggest reason is performance. We are a company that really focuses on driving pleasure." Link1

And this about torque: Link2
 

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Goran Dzepina, look this:
MAZDA'S AKIRA MARUMOTO:
"The engine really achieves good performance through high-octane gasoline. We were considering just using regular gasoline. But we decided to recommend high-octane premium gasoline for the Skyactiv-X. The biggest reason is performance. We are a company that really focuses on driving pleasure." Link1
In the UK Mazda recommend 95 RON for both the 2.0G and 2.0X
I think that is what he means by "high-octane premium". In the UK 95 (regular) is the lowest available but many countries go lower, hence his description as high.
 

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Well, here in Bulgaria Mazda also recommends 95 RON.
But I tried 2 tanks 100 RON in my 2.0G. I felt the car perfect - more torque and noticeably quieter engine.
I never knew if it was okay with the engine and went back to 95.
 

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In my view we are now in the era of smaller displacement) turbocharged 4 cylinder direct-injected engines as a "baseline"... a given. Mazda does not really have one, except for the 2.5T (large displacement) which is not distributed in Europe (for the 3) or for that matter - anywhere (yet). I'm not yet convinced that SkyActiv-X is truly smooth. With a normally aspirated engine (or the X's light supercharger) you WILL have to spin up the engine (versus just put your foot in it - with the aforementioned turbo) if you want some "jam".
 

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Has anyone tested Shell V-Power with the Skyactiv-X ?
V Power is high octane fuel, the equivalent of 93 octane in the US. High octane would not work well in the SA-X. While conventional engines have sensors to prevent pre-ignition, the SA-X actually uses the principles of pre-ignition to function. Higher octane fuel is more knock resistant, so the lean burn compression ignition would have problems.

With a normally aspirated engine (or the X's light supercharger) you WILL have to spin up the engine (versus just put your foot in it - with the aforementioned turbo) if you want some "jam".
The lean burn assist supercharger (the official Mazda term is High Response Air Supply) isn't dependent on engine speed. Its driven by an electric clutch and engages only when needed.
 

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But accelerate between 3.000 and 6.000 rpm doesn’t go smoothly. It feels a bit irregular and with little shocks. I did a test drive in another Skyactiv-x car and I felt the same. I personaly hope a software update will fix this problem. What did you experience yourself while testdriving?
Check the below video. It is a series of many Mazde 3 videos with all engines available with consumption comparison over numerous routes.
At 5:40 you can see the below dyno test, the only one available so far. Even though I am not sure of the fuel used, it should explain the underwhelming mid range performance which was by the way also confirmed by myself during my 2 test drives here in Greece. Let's hope this will be sorted with a software update making the transition from SPCCI to normal combustion more linear. Hoping for more detailed responses to help all the future buyers, myself included.
275041
 

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Seen that video yesterday. Interesting, what could be the reason for such a drop in the middle of the rev range?
I think this is the range where transition from SPCCI to classic spark ignition occurs ....
 

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Seen that video yesterday. Interesting, what could be the reason for such a drop in the middle of the rev range?
I think this is the range where transition from SPCCI to classic spark ignition occurs ....
Yes, that is the case. This is why, if the above is considered to be an issue, mazda could probably address it with a software update. That is my guess
 

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V Power is high octane fuel, the equivalent of 93 octane in the US. High octane would not work well in the SA-X. While conventional engines have sensors to prevent pre-ignition, the SA-X actually uses the principles of pre-ignition to function. Higher octane fuel is more knock resistant, so the lean burn compression ignition would have problems.
This theory sounds plausible if your knowledge is limited to a world where engines were mechanically controlled. Modern engines have an array of sensors and a lot of computing power. The ECU would be closely monitoring several factors such as exhaust gas temperature, the knock sensor, etc, making adjustments as necessary. This level of monitoring would enable the engine to take the fuel grade into account.

In any case it is inconceivable that Mazda would release their new, state-of-the-art engine knowing that it might have problems due to using fuel which is "too good", let alone do so without bothering to warn owners. Such a warning would be important because, at least in the UK, many drivers choose V Power or its equivalent from other brands in the belief that their enhanced additive packages prolong engine life/performance and not because they need the higher octane rating. The belief is there because that is how the companies advertise these fuels and justify their considerable extra cost.
 

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Mazda oversold the x from the git go. It does not deliver either the power or fuel economy promised. Thankfully we are not stuck with this dog in the US. Yet.. Even the old 2.0 sky G engine sold here was a lot better performer claiming only 155 hp. It's so complex and radical it must have taken a large portion of their meager resources to get it launched. Given the company size, they would have been better off to purchase engines from sombody bigger that already has something on the shelf. There are some good ones out there. With their small production numbers, no need to keep retooling factories each time tech advances.
 

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This theory sounds plausible if your knowledge is limited to a world where engines were mechanically controlled. Modern engines have an array of sensors and a lot of computing power. The ECU would be closely monitoring several factors such as exhaust gas temperature, the knock sensor, etc, making adjustments as necessary. This level of monitoring would enable the engine to take the fuel grade into account.

In any case it is inconceivable that Mazda would release their new, state-of-the-art engine knowing that it might have problems due to using fuel which is "too good", let alone do so without bothering to warn owners. Such a warning would be important because, at least in the UK, many drivers choose V Power or its equivalent from other brands in the belief that their enhanced additive packages prolong engine life/performance and not because they need the higher octane rating. The belief is there because that is how the companies advertise these fuels and justify their considerable extra cost.
This isn't a theory. The SA-X engine uses the principles of pre-ignition to function in SCCI mode. No engine sensor can make fuel more or less prone to knock. Premium fuel will work but might not work as well as the mid grade that is required by Mazda.
You need to realize that the SA-X is not a conventional engine, so conventional gas engine thinking does not apply.

Seen that video yesterday. Interesting, what could be the reason for such a drop in the middle of the rev range?
I think this is the range where transition from SPCCI to classic spark ignition occurs ....
Mazda engines have for years exhibited a mid-range dip like that. Much of it is because of the intake design. The harmonics of the intake create resonance waves at certain rpms that can impede airflow. This is why the intakes have Helmholz chambers designed into them. The chambers are supposed to nullify much of the resonance, but its possible that its still present to some extent.
 

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Posting here measurements from adac.de for 2l SkyActiv-G 122HP, 2l SkyActiv-X 180HP and 1.5l turbo 182HP from Honda Civic (as a reference) in this order.
What I can see is that the Civic has the best acceleration and also fuel consumption and SkyActiv-X is just a small improvement from SkyActiv-G but stands no chance in terms of performance against competition from similar 180HP from Civic or 1.8TSI Skoda/Seat/VW.
Screen Shot 2020-01-19 at 7.37.55 AM.png

Screen Shot 2020-01-19 at 7.38.00 AM.png

Screen Shot 2020-01-19 at 7.38.36 AM.png
 

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Those figures are consistent with the compilations of real world data that I linked previously.

In the UK the only current options are 2.0G and 2.0X (both M Hybrid)* and all the data confirm my decision to buy the 2.0G because I could see little if any gain in normal (UK) driving from the new engine. I would also advise anyone in the UK wanting a performance car to look elsewhere.
* Mazda withdrew the diesel option towards the end of last year.

I have not seen any real world data for the 2.5G engine but I guess that makes the 2.0X an even less attractive purchase in markets where it is available.
 

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So guys, someone suggested me an software optimization for the SA-X which would bring the car to 205HP and 250 N/m torque.
They said they will achieve this by changing the AF (Air/Fuel) ratio, ignition advance and cam timing. What do you think? Would this benefit the car maybe?

Coming from a Mazda 3 2014 HB with the 2.2 bi-turbo diesel engine which I tuned to 190 HP and 470 N/m which you could really feel, the new SA-X seems disappointing at least specs wise. When I test drove it, it felt more sluggish than my last engine (I mean ofc compare 225 N/m to 470), but at the same time I felt that it would be enough for day to day driving and it was somehow more fun since I could rev it up more. Now I agree that this new engine should have proven better results because it was so hyped up,but you also have to take in consideration that the car is heavier than the previous generation (Mazda 3 2014 has 1320 kg FWD while the SA-X AWD that I ordered has 1467kg, awd adds weight ofc) also this car is naturally aspirated so you do not have the boost from the turbo, I have seen someone here comparing the 1.5l turbo of the Honda, I mean ofc it will prove faster if it has a turbo, but this is also a matter of choice and let me tell you why. While I enjoyed my last car engine, I was let down by so many things on the car itself such as NVH levels in it, the tire noise was absurd and it was lacking so many features.. What convinced me to buy the new one was not the engine (did not do a lot of research about it to be honest), but all the changes they've done which filled my complaints about my last one. Do I think it's cool now that the engine it's not satisfying? Heck no, but I prefer a less satisfying engine rather than a satisfying one and a lots of other complaints. Would I prefer a Honda over a Mazda just because of that better performance sheet of their engine? No , but again this is a matter of choice. If you are buying a Mazda for it's performance and 0-100 times I think you should look somewhere else. I myself have settled to the fact that this is not a performance and a car that you can tune to reach some really nice figures. For that , probably I will buy another car. Mazda cannot satisfy absolutely every aspect that we buyers want, especially with the prices they are at. Also, keep in mind that HP does not necessarily mean a car it's fast. Put a 200 hp engine in an 1700kg car and you will say the same. I am not backing up this engine at all, I am as disappointed as all of you guys, but at the same time, lets say this engine is somewhere at 3/5 on an expectation scale. Would you rather not buy it because of this or buy a 5/5 expectation alternative that does not fill the other gaps? Again, it's all about what we are willing to accept
 
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