HP of the Turbo on 91, vs 87 or 93?

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Phoenix
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227 hp on 87, 250 with premium, how much with 91 rather than 93. What does Mazda consider premium? AZ premium is 91. Is someone going to say 240hp on 91 octane?
 
I don't think there's dyno-backed answer to your question but it will be insignificant change that you won't feel from everyday driving.
 
Whenever people say you won't notice a change in your powerband because it's "insignificant", it tells me that person doesn't really pay attention to how their engine is performing and when (gear/rpm/throttle). There is certainly nothing insignificant about the ability of a higher octane fuel to maintain power in less than ideal conditions compared to a lower (certainly the lowest) specified fuel, especially when you factor in the huge effect changes in temperature on engine performance.

I notice almost any change in my engines performance at any RPM because I have learned) and expect a certain level of performance at various RPMs and gears under "normal" conditions. These RPMS and throttle settings tend to be pretty consistent because your driving habits are generally consistent. Any deviation, whether it's due to lower quality fuel, much cooler or hotter weather, etc is certainly noticed. Personally, I would not pay a premium for a stronger (albeit gimped) motor just to operate it at a lower performance.
 
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hal2, I don't know if the relationship between octane rating and horsepower is linear, but there is a 23 HP difference between 87 and 93 octane so that is close to 4 HP for every 1 increase in octane. So maybe 241-242 HP on 91 octane ? Certainly better than 227 HP and less prone to pinging if you come close to lugging the engine which you shouldn't do anyway.
91 octane is the highest available here in CA too and is all that I use in my CX 5 turbo. I'm with Chris_Top_Her regarding fuel choice philosophy.
 
I agree with the other posters in assuming that its around 242 with 91. I only have 91 available to me, and there is a perceptible difference in power between 87 and 91 once you get into the higher RPM range. I don't have any data to back my claim, all I can say is that I can notice it, so take that for what it's worth.
 
I agree with the other posters in assuming that its around 242 with 91. I only have 91 available to me, and there is a perceptible difference in power between 87 and 91 once you get into the higher RPM range. I don't have any data to back my claim, all I can say is that I can notice it, so take that for what it's worth.

I timed the 20-80mph acceleration on my vehicle with 87, 91, and 93 octane. Then I put the SRA intake on it. This is dyno proven 10whp. With 91 octane and the SRA, it was SLIGHTLY quicker than with 93 octane and OEM intake. With the 87 octane, it was slower than the 91 by a larger margin than 91 was the 93. Proportionately, all the #'s stacked exactly with 10whp for the SRA proven by Corksport, and 87/227 and 93/250 and 91/242. Had a bit to drink, so figure it out. Sorry it's jumbled.
 
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