94 Octane > 91 Octane S/C mpg?

Okay, first off I do know what Octane rating is so I'm not here to discuss the fact that it has nothing to do with the amount of energy in the gasoline. If you came here to post about that there are tons of other Octane related threads for you to go sound smart on. If you want to give me some good input to my following situation, keep reading:

So on Good Friday I had to deliver some rims and tires from my wifes old car I sold on Kijiji to a guy who lives about an hour away in Medicine Hat, AB. On my way there I was burning my usual 91 Octane gas from CO-OP. CO-OP has top tier gasoline and it has always yielded the same or better MPG as Shell, Esso, Fastgas, etc in the past. If you don't know wht top tier means check here: http://www.toptiergas.com/ . It's pretty much a standard on the quality of additives in gas. Anyways on my way to Medicine Hat I was getting about 14 mpg with a slight tail wind which is close to my norm of 15 mpg highway with my S/C and 33" tires.

When I dropped off the tires I had about an 1/8th of a tank so I had to gas up for the ride home. I decided to go to Costco gas to save money but my Google Maps screwed up and lead me a bit off the beaten path. On my way I found a Petro Canada, decided to screw driving any further, and gassed up there. They had the 94 Super, which I had ran a few times in my old Nissan Juke but not my Tacoma, and I decided for the extra 3 cents a liter I would splurge.

The weird thing is on my way home, with a slight head wind, I was getting close to 17 mpg... I understand that four car tires on alloy rims is about 100-120 lbs of weight but still +3 mpg's into the wind is a lot of mileage.

So has anyone else experienced this? My local Petro Canada doesn't usually carry 94 but now I'm thinking about fueling up with 94 any chance I get to. Maybe the Petro Canada 94 isn't winter gas or something? I'm just wondering if anyone else has had a similar experience on a S/C'd Tacoma getting better mileage on higher octane gas...

 

Running higher octane fuel would let you use less fuel to fight detonation and retard timing less. Its more noticable on boosted engines.

 

I run 94 from chevron, I like the fact no ethanol is added, and my mileage is pretty good compared... 1-2 miles per gallon. I will say that here the price per liter is only 3 cents different. I don't buy my gas in the states due to the ethanol. Found it affected my performance, but could have just been subjective.

 

I should say 91 is the standard for Premium gasoline in Canada. 94 is only offered at select PetroCanada stations. I also know that Shell and COOP are the only two companies to offer no ethanol in there 91 gas here. That's why I run COOP 91 usually. I'm not sure if the PetroCanada 94 has ethanol or not, I know their 91 does so I don't run it.

I totally get that. On an engine designed for 91 it shouldn't matter though right? Or can our Tacoma advance the timing far enough that 94 is better for the stock TRD tune?

Or could it be possible, and if anyone in here has a S/C from Canada maybe they know this, that PetroCanada isn't putting ethanol in their 94 like they do in the 91 and the 94 is not a winter fuel? I think COOP here is still on winter gas, so I could see that effecting mpg too.

Normally I'd just figure this out myself over the summer, but I don't have a 94 station nearby and I'd like to know more about any known differences before I start seeking them out on trips out of town.

 

Husky carries ethanol free 91 too

 

Interesting. Here there pumps are still marked up to 10% ethanol right below the premium sticker. At least, last year when I filled up there they were. I think they offered 93 octane as there premium too but I assumed it was because of the ethanol.

OZ, do you know anything about the PetroCanada 94 stuff? I'm having trouble finding out if there's anymore to it than it's octane rating. The stuff I have found shows that it is popular with some BMW and other premium running cars and some swear it gets better mpg's than there 91, but no one is really figuring out why. Is it tune, components, or something else?

 

Found this on Husky premium:

A selection of octane levels to suit your needs

• Octane 87. Regular with ethanol (available in all provinces)
• Octane 89. Mid-grade (regular blended with premium, available in all provinces)
• Octane 91. Premium - no ethanol (available in all provinces)
• Octane 91. Premium with ethanol (London, Ontario area only)
• Octane 92. Premium with ethanol (SK & MB)
• Octane 94. Premium Plus with ethanol, the highest octane fuel available (AB, SK & MB)

My local station only offers 94 for premium, so it is ethanol blended.

Found this on PetroCanada 94:

What does this mean for your vehicle? Ultra 94's unique performance and higher detergency helps to:

• Clean your car's fuel injectors and intake valves — and keep them clean
• Optimize fuel economy
• Reduce emissions
• Improve overall vehicle performance year-round

The last part makes me think it is unique in that it is not winter gas. It's company BS but they do have to back it up somehow so making it a universal fuel year round would make sense. I also learned that 94 from them is only offered in Alberta and Ontario, and Medicine Hat at 100 km away is the closest station so I won't be looking out for it. I think COOP and Shell have a winter formula premium and that is where the mileage difference is coming from because I do know that I get closer to 17 mpg in summer with Shell or COOP gas.

 

Similar to you, My supercharger hate, but realy hate the winter blend. It kills my MPG to something similar to you, like 13.5-14 mpg. In summer my MPG is more like 16-16.5 mpg.

And like you, my supercharger realy like the petrocan 94 and like you it is not available close to me. It's not available in the Québec city area. So when going to Montréal, doing a stop at the petrocan