Regular gas in the Mazda 3

[tundraotto]

^ yes

In my 2014 Mazda6 2.5L Skyactiv I noticed more power with 91 octane vs 87, more timing advance allowed.

40-60miles more per tank of fuel.

not quite enough to offset the cost difference - but there is a power and mpg benefit.

 

[PimTac]

Originally Posted by tundraotto
^ yes

In my 2014 Mazda6 2.5L Skyactiv I noticed more power with 91 octane vs 87, more timing advance allowed.

40-60miles more per tank of fuel.

not quite enough to offset the cost difference - but there is a power and mpg benefit.




To be honest, while these engines run very well on 87, I also found a difference in performance and fuel economy running Shell V Nitro. The computer will compensate.

 

[quint]

In our 2017 with the 2.5, in very hot weather, in city driving the engine is certainly way smoother with 93 as compared to 87. In cooler weather I cant really say I notice any major difference at all between regular and premium so 99.9% of the time I fill up, its getting 87. Most of my driving is highway anyway and a slight increase in power or a dozen or two miles per tank gets lost in the noise so I don't bother with higher octane too much, Skyactiv's seem to do fine on 87.

 

[Ws6]

Originally Posted by Olas
Originally Posted by Rolla07
No point using 91 unless it says to in manual. The price difference in Canada is crazy... the other day it was 20 cents a liter...most cars use 87...if it caused any rust to the internals we'd of known by now.


All cars made in the last 20 years have computer controlled timing and knock sensors, so there is ALWAYS benefit to using higher octane levels.

With the Mazda 3, that benefit is about 2 horsepower, as measured on a dyno, lol!

Here is a Miata (similar engine, albeit a touch smaller, but the SkyActiv family is the same.

https://newsroom.aaa.com/wp-content...uel-Phase-II-Research-Report-FINAL-2.pdf

 

[Olas]

Originally Posted by Ws6
Originally Posted by Olas
Originally Posted by Rolla07
No point using 91 unless it says to in manual. The price difference in Canada is crazy... the other day it was 20 cents a liter...most cars use 87...if it caused any rust to the internals we'd of known by now.


All cars made in the last 20 years have computer controlled timing and knock sensors, so there is ALWAYS benefit to using higher octane levels.

With the Mazda 3, that benefit is about 2 horsepower, as measured on a dyno, lol!


Yep, more power and more MPG. And more is always better. There is no reason to use cheap swill in an engine designed to take advantage of higher octane, you are throwing away money and performance.

 

[Ws6]

Originally Posted by Olas
Originally Posted by Ws6
Originally Posted by Olas
Originally Posted by Rolla07
No point using 91 unless it says to in manual. The price difference in Canada is crazy... the other day it was 20 cents a liter...most cars use 87...if it caused any rust to the internals we'd of known by now.


All cars made in the last 20 years have computer controlled timing and knock sensors, so there is ALWAYS benefit to using higher octane levels.

With the Mazda 3, that benefit is about 2 horsepower, as measured on a dyno, lol!


Yep, more power and more MPG. And more is always better. There is no reason to use cheap swill in an engine designed to take advantage of higher octane, you are throwing away money and performance.



You do understand that 2 horsepower is meaningless, but the hundreds of dollars could have bought you some taco bell or sumthin, right?

 

[Olas]

.[/quote]

You do understand that 2 horsepower is meaningless, but the hundreds of dollars could have bought you some taco bell or sumthin, right?[/quote]

How many multiples of 2hp do oyu need for it to not be worthless? your 600hp muscle car only has 300 multiples of 2hp, but if 2hp is meaningless you could take away all 300 of them and it wouldnt make any difernece, right?

No hp is worthless, hp is defined as the ability to do work. You need to brush up on your engineering principles.

 

[Ws6]

Originally Posted by Olas
.


You do understand that 2 horsepower is meaningless, but the hundreds of dollars could have bought you some taco bell or sumthin, right?[/quote]

How many multiples of 2hp do oyu need for it to not be worthless? your 600hp muscle car only has 300 multiples of 2hp, but if 2hp is meaningless you could take away all 300 of them and it wouldnt make any difernece, right?

No hp is worthless, hp is defined as the ability to do work. You need to brush up on your engineering principles.[/quote]

Engineering has, and always will, bow to economics and actual practice. NO sense spending $10/tank more when you can just under-fill the tank by 1/4 and achieve the same gains in acceleration.

 

[DBMaster]

I have been using E15 in mine for over a year. In the summer it "seems" to reduce the lag when accelerating from a stop. It could be in my head, or a result from the "butt dyno" that peple reference here all the time. The octane rating is 88 versus 87. The fuel economy readings I get are virtually unchanged compared to E10.