AVG MPG in a 2.0 Skyactiv
- Thread starter buster
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Wow, not too bad at all.
I've read the 'technical communication' PDF from Dave Coleman you posted. Very interesting imho.
Mazda's North American HQ is just down the road btw.
Its amateur motorsports parts program (wholesale pricing for active participants) is excellent and builds loyalty to the marque.
Sizable discounts for new vehicle purchases as well.
Seems all those little incremental slices stack up to manifest reduced consumption.
I've read the 'technical communication' PDF from Dave Coleman you posted. Very interesting imho.
Mazda's North American HQ is just down the road btw.
Its amateur motorsports parts program (wholesale pricing for active participants) is excellent and builds loyalty to the marque.
Sizable discounts for new vehicle purchases as well.
Seems all those little incremental slices stack up to manifest reduced consumption.
gathermewool
Site Donor 2025
Originally Posted By: badtlc
Originally Posted By: gathermewool
Why not 87 octane? V-Power is only offered in the highest octane, right? Around here, that's 93. If that thing calls for 87 AKI, what's the benefit of using multiple tiers higher?
This has been covered many times but modern engines, especial DI engines have the ability to control AF ratio in addition to timing based on octane. If you run premium in a skyactiv, it not only advances timing but leans out the AF ratio which improves MPGs and reduces fuel dilution in the oil.
When running 87 in such a high compression engine, the ECU has to run pig rich to keep the combustion chamber temps down and prevent detonation. It works fine but there are better options if you prefer.
Was it covered by you and other members or by a tuner and/or some white paper?
If the ECU tables only allow for fueling, ignition timing, and valve timing based on 87 octane (or slightly higher) it literally cannot account for the higher octane. The ECM should attempt to advance ignition timing, adjust fueling and vary valve timing to the the threshold of knock. If 87 octane fuel is beyond this threshold, then even using 89 would be a waste. If 89 is more appropriate for a skyactiv motor, then 91 would be a waste.
Not every state offers 93 octane and some states only offer an inferior 91 AKI as their premium fuel, so it's hard for me to believe (maybe wrongly) that a manufacturer would tune an engine to take advantage of this much variability without so much as recommending a higher octane than 87, even if it was solely to gain that extra bit for marketing purposes. Mazda does only recommend 87 or higher, right?
So, I guess I'm asking how you know that your ECM is taking advantage of premium fuel. I'm very interested in a Mazda as my next vehicle, and would love to know of any hidden gems that would make owning one that much cooler.
Originally Posted By: gathermewool
Why not 87 octane? V-Power is only offered in the highest octane, right? Around here, that's 93. If that thing calls for 87 AKI, what's the benefit of using multiple tiers higher?
This has been covered many times but modern engines, especial DI engines have the ability to control AF ratio in addition to timing based on octane. If you run premium in a skyactiv, it not only advances timing but leans out the AF ratio which improves MPGs and reduces fuel dilution in the oil.
When running 87 in such a high compression engine, the ECU has to run pig rich to keep the combustion chamber temps down and prevent detonation. It works fine but there are better options if you prefer.
Was it covered by you and other members or by a tuner and/or some white paper?
If the ECU tables only allow for fueling, ignition timing, and valve timing based on 87 octane (or slightly higher) it literally cannot account for the higher octane. The ECM should attempt to advance ignition timing, adjust fueling and vary valve timing to the the threshold of knock. If 87 octane fuel is beyond this threshold, then even using 89 would be a waste. If 89 is more appropriate for a skyactiv motor, then 91 would be a waste.
Not every state offers 93 octane and some states only offer an inferior 91 AKI as their premium fuel, so it's hard for me to believe (maybe wrongly) that a manufacturer would tune an engine to take advantage of this much variability without so much as recommending a higher octane than 87, even if it was solely to gain that extra bit for marketing purposes. Mazda does only recommend 87 or higher, right?
So, I guess I'm asking how you know that your ECM is taking advantage of premium fuel. I'm very interested in a Mazda as my next vehicle, and would love to know of any hidden gems that would make owning one that much cooler.
Originally Posted By: buster
2015 3 with the 2.0. 6 spd MT. 80-85 mph.
Thanks, one more question.
Is this mpg average from the dash read out only?
2015 3 with the 2.0. 6 spd MT. 80-85 mph.
Thanks, one more question.
Is this mpg average from the dash read out only?
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Originally Posted By: gathermewool
Was it covered by you and other members or by a tuner and/or some white paper?
If the ECU tables only allow for fueling, ignition timing, and valve timing based on 87 octane (or slightly higher) it literally cannot account for the higher octane. The ECM should attempt to advance ignition timing, adjust fueling and vary valve timing to the the threshold of knock. If 87 octane fuel is beyond this threshold, then even using 89 would be a waste. If 89 is more appropriate for a skyactiv motor, then 91 would be a waste.
Not every state offers 93 octane and some states only offer an inferior 91 AKI as their premium fuel, so it's hard for me to believe (maybe wrongly) that a manufacturer would tune an engine to take advantage of this much variability without so much as recommending a higher octane than 87, even if it was solely to gain that extra bit for marketing purposes. Mazda does only recommend 87 or higher, right?
So, I guess I'm asking how you know that your ECM is taking advantage of premium fuel. I'm very interested in a Mazda as my next vehicle, and would love to know of any hidden gems that would make owning one that much cooler.
It is in some manufacturing data if you scour the internet enough. Much of it has been posted on here and discussed many times.
I also tested it my previous Mazda3. UOA on 87 octane had typical fuel dilution issues. On 91+ octane, fuel dilution was completely gone and MPGs went up by over 1 MPG.
try looking up how engines handle flex fuels as a starting point.
Was it covered by you and other members or by a tuner and/or some white paper?
If the ECU tables only allow for fueling, ignition timing, and valve timing based on 87 octane (or slightly higher) it literally cannot account for the higher octane. The ECM should attempt to advance ignition timing, adjust fueling and vary valve timing to the the threshold of knock. If 87 octane fuel is beyond this threshold, then even using 89 would be a waste. If 89 is more appropriate for a skyactiv motor, then 91 would be a waste.
Not every state offers 93 octane and some states only offer an inferior 91 AKI as their premium fuel, so it's hard for me to believe (maybe wrongly) that a manufacturer would tune an engine to take advantage of this much variability without so much as recommending a higher octane than 87, even if it was solely to gain that extra bit for marketing purposes. Mazda does only recommend 87 or higher, right?
So, I guess I'm asking how you know that your ECM is taking advantage of premium fuel. I'm very interested in a Mazda as my next vehicle, and would love to know of any hidden gems that would make owning one that much cooler.
It is in some manufacturing data if you scour the internet enough. Much of it has been posted on here and discussed many times.
I also tested it my previous Mazda3. UOA on 87 octane had typical fuel dilution issues. On 91+ octane, fuel dilution was completely gone and MPGs went up by over 1 MPG.
try looking up how engines handle flex fuels as a starting point.
As mentioned above, the DI high compression engines do respond well to premium fuels.
Even my Ecoboost F150 gets 1MPG+ more with premium. Drives better too. It costs no more to use premium!
Interestingly, I cannot drive carefully enough to make up for the lost MPG of regular. The MPG simply goes down on regular.
Even my Ecoboost F150 gets 1MPG+ more with premium. Drives better too. It costs no more to use premium!
Interestingly, I cannot drive carefully enough to make up for the lost MPG of regular. The MPG simply goes down on regular.
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I have posted it a few times on here as well - but my parents' 2013 Escape with 2.0L ecoboost engine got a very significant jump in fuel economy (they live in a hilly area) from going to 91 from 87. It can eek out 30MPG with 91 ethanol free. Not bad considering it's nearly 4000 pounds, AWD, has slushbox, etc
gathermewool
Site Donor 2025
Originally Posted By: badtlc
Originally Posted By: gathermewool
Was it covered by you and other members or by a tuner and/or some white paper?
If the ECU tables only allow for fueling, ignition timing, and valve timing based on 87 octane (or slightly higher) it literally cannot account for the higher octane. The ECM should attempt to advance ignition timing, adjust fueling and vary valve timing to the the threshold of knock. If 87 octane fuel is beyond this threshold, then even using 89 would be a waste. If 89 is more appropriate for a skyactiv motor, then 91 would be a waste.
Not every state offers 93 octane and some states only offer an inferior 91 AKI as their premium fuel, so it's hard for me to believe (maybe wrongly) that a manufacturer would tune an engine to take advantage of this much variability without so much as recommending a higher octane than 87, even if it was solely to gain that extra bit for marketing purposes. Mazda does only recommend 87 or higher, right?
So, I guess I'm asking how you know that your ECM is taking advantage of premium fuel. I'm very interested in a Mazda as my next vehicle, and would love to know of any hidden gems that would make owning one that much cooler.
It is in some manufacturing data if you scour the internet enough. Much of it has been posted on here and discussed many times.
I also tested it my previous Mazda3. UOA on 87 octane had typical fuel dilution issues. On 91+ octane, fuel dilution was completely gone and MPGs went up by over 1 MPG.
try looking up how engines handle flex fuels as a starting point.
Yep, I'm aware of how flex fuel can result in increased power (85% is pretty knock-resistant) but that not even close to the same as DI-effect. I'm still not sure why Mazda would not at least recommend higher octane, were it not beneficial.
Others: a forced induction DI engine is way off-topic. Forced induction using 87 octane is only possible due to DI. The DI is not what provides a benefit when premium fuel is used - it's the turbo. IMO, any turbo engine should be run on premium. Why waste time on lower octane where the ECU is holding something back due to lower octane use.
Originally Posted By: gathermewool
Was it covered by you and other members or by a tuner and/or some white paper?
If the ECU tables only allow for fueling, ignition timing, and valve timing based on 87 octane (or slightly higher) it literally cannot account for the higher octane. The ECM should attempt to advance ignition timing, adjust fueling and vary valve timing to the the threshold of knock. If 87 octane fuel is beyond this threshold, then even using 89 would be a waste. If 89 is more appropriate for a skyactiv motor, then 91 would be a waste.
Not every state offers 93 octane and some states only offer an inferior 91 AKI as their premium fuel, so it's hard for me to believe (maybe wrongly) that a manufacturer would tune an engine to take advantage of this much variability without so much as recommending a higher octane than 87, even if it was solely to gain that extra bit for marketing purposes. Mazda does only recommend 87 or higher, right?
So, I guess I'm asking how you know that your ECM is taking advantage of premium fuel. I'm very interested in a Mazda as my next vehicle, and would love to know of any hidden gems that would make owning one that much cooler.
It is in some manufacturing data if you scour the internet enough. Much of it has been posted on here and discussed many times.
I also tested it my previous Mazda3. UOA on 87 octane had typical fuel dilution issues. On 91+ octane, fuel dilution was completely gone and MPGs went up by over 1 MPG.
try looking up how engines handle flex fuels as a starting point.
Yep, I'm aware of how flex fuel can result in increased power (85% is pretty knock-resistant) but that not even close to the same as DI-effect. I'm still not sure why Mazda would not at least recommend higher octane, were it not beneficial.
Others: a forced induction DI engine is way off-topic. Forced induction using 87 octane is only possible due to DI. The DI is not what provides a benefit when premium fuel is used - it's the turbo. IMO, any turbo engine should be run on premium. Why waste time on lower octane where the ECU is holding something back due to lower octane use.
ls1mike
$50 Site Donor 2025
So it is a manual? Man that is good! How heavy is it? The Malibu is a 259 HP 2.0 turbo and will see about 32 to 35 MPG going 70 to 75.
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Originally Posted By: gathermewool
Yep, I'm aware of how flex fuel can result in increased power (85% is pretty knock-resistant) but that not even close to the same as DI-effect. I'm still not sure why Mazda would not at least recommend higher octane, were it not beneficial.
Are you perhaps new to the United States?
Yep, I'm aware of how flex fuel can result in increased power (85% is pretty knock-resistant) but that not even close to the same as DI-effect. I'm still not sure why Mazda would not at least recommend higher octane, were it not beneficial.
Are you perhaps new to the United States?
I'd like a 3 hatch but worried about reliability or valuation north of 150k C&Driver sure loves the whole line-up new out of the box...just don't see or hear of many hi-mileage examples of Mazda..gives me pause to a real temptation to buy.
Originally Posted By: dblshock
I'd like a 3 hatch but worried about reliability or valuation north of 150k C&Driver sure loves the whole line-up new out of the box...just don't see or hear of many hi-mileage examples of Mazda..gives me pause to a real temptation to buy.
I have about 137k miles on my Mazda 3 and no major issues to report. Great car all around.
Why you don't hear many reports is because compared to the major players, Mazda sales are but a tiny portion. Corolla alone probably outsells the whole Mazda lineup and then some.
I'd like a 3 hatch but worried about reliability or valuation north of 150k C&Driver sure loves the whole line-up new out of the box...just don't see or hear of many hi-mileage examples of Mazda..gives me pause to a real temptation to buy.
I have about 137k miles on my Mazda 3 and no major issues to report. Great car all around.
Why you don't hear many reports is because compared to the major players, Mazda sales are but a tiny portion. Corolla alone probably outsells the whole Mazda lineup and then some.
Originally Posted By: dblshock
I'd like a 3 hatch but worried about reliability or valuation north of 150k C&Driver sure loves the whole line-up new out of the box...just don't see or hear of many hi-mileage examples of Mazda..gives me pause to a real temptation to buy.
I hear you. Well, there are quite a few people now with well over 100k miles on the Skyactiv engines. One guy has 165k and has had no problems. Not really sure how reliable they are compared to Honda/Toyota.
I know that all the Mazda 3's we have had over the years never consumed any oil, which was nice. My Honda/Toyotas always did.
FYI the rpms at 85 mph in 6th gear are exactly 3,000. That's good for a 4cyl.
I'd like a 3 hatch but worried about reliability or valuation north of 150k C&Driver sure loves the whole line-up new out of the box...just don't see or hear of many hi-mileage examples of Mazda..gives me pause to a real temptation to buy.
I hear you. Well, there are quite a few people now with well over 100k miles on the Skyactiv engines. One guy has 165k and has had no problems. Not really sure how reliable they are compared to Honda/Toyota.
I know that all the Mazda 3's we have had over the years never consumed any oil, which was nice. My Honda/Toyotas always did.
FYI the rpms at 85 mph in 6th gear are exactly 3,000. That's good for a 4cyl.
Originally Posted By: buster
FYI the rpms at 85 mph in 6th gear are exactly 3,000. That's good for a 4cyl.
Originally Posted By: buster
43.4 mpg avg on commute home. Shell VPower.
It's hard to believe an engine is turning at 3,000 RPM at 85 MPH and still gets 40 MPG. If it is at 2,000 RPM then 40 MPG is easy to understand.
FYI the rpms at 85 mph in 6th gear are exactly 3,000. That's good for a 4cyl.
Originally Posted By: buster
43.4 mpg avg on commute home. Shell VPower.
It's hard to believe an engine is turning at 3,000 RPM at 85 MPH and still gets 40 MPG. If it is at 2,000 RPM then 40 MPG is easy to understand.
Sam Haymart from TestdrivenTV(YouTube) tested a '14 Mazda3 sedan for fuel economy and actually got ~ 2 MPG better than the trip computer. IIRC, he got over 46 MPG with a SkyActiv 2.0 auto. Sam does claim that he did drive the for MPG by driving the speed limit and mostly highway.
https://www.youtube.com/watch?v=eXYJ5jGE37k
https://www.youtube.com/watch?v=eXYJ5jGE37k
There is no tachometer in Mazda 3 with auto transmission in the video ?
Originally Posted By: HTSS_TR
There is no tachometer in Mazda 3 with auto transmission in the video ?
Some trim levels of the Mazda 3 do have the tach, while others don't.
BC.
There is no tachometer in Mazda 3 with auto transmission in the video ?
Some trim levels of the Mazda 3 do have the tach, while others don't.
BC.
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