Best Premium Fuel Brand for Top Gas Mileage?

One of my favorite talking points with car enthusiasts when speaking about my Mazda MX-5 Miata is the awesome fuel mileage I get, which usually results in some snarky comment how you’re not meant to notice gas mileage in a sports car… Well, on my latest Canadian Road Trip to marshal at Mosport I set out to test whether cheaper/lower ranked Speedway fuel was better than BP premium fuel I typically use. I noticed this phenomena on my last 3,000+ mile road trip to Florida and with 1,000+ miles done on this trip it was easy to see what was what.  Or so I thought.

What did I discover?

Something most people probably already know… there’s little difference between the different brands of fuel and gas mileage can vary from the same brand gotten at different stations, depending on weather conditions, driving style, road terrain, etc.

I found that Speedway fuel is sufficient for me to use on most road trips where Speedway fuel is available because it does yield better gas mileage than ultimate 93 from BP (the one closest to my house).

However, when driving around town I find BP fuel gives far better performance than Speedway gas does which almost seems sluggish.

And those findings may make sense to some, while others will probably brush this very unscientific observation off. Speedway doesn’t have as many additives, and as such it probably burns at a slower rate which yields decent gas mileage when the car is cruising at highway speeds. However, when used in stop and go traffic especially during times where peppy acceleration is required it doesn’t perform as well. While BP fuel has more additives and therefore performs better when the right foot gives the gas pedal a workout, but on longer trips on the highway it is burned at a quicker rate without necessarily providing any additional performance boost. Or so I think…

The figures from my last Road Trip to Canada are as follows:

5/18 speedway paramus 9.760 @ 2.459/gal = $24.00
5/19 speedway cicero 7.779 @ 2.699/gal = $21.00
5/19 shell canada 27.155 @ 1.289/L = C$35.00
5/23 petro-canada 14.929 @ 1.239/L = C$18.50
5/23 speedway cicero 7.595 @ 2.699/gal = $20.50
5/24 speedway paramus 8.634 @ 2.399/gal = $20.71

Based on the conversion rate at the time, I spent $126.96 USD on a 1,155 mile Road Trip at an average of almost 33 mpg. I spent $86 USD and $54 CAD. I filled up 24 gallons in US and just over 11 in Canada, or better yet I put in 42 Liters in Canada (which probably wasn’t necessary considering I paid almost $10 US more per tank fuel up in Canada than I do here in New Jersey. But I did want to try their gas, and specifically Ultra94 from Petro-Canada which was advertised on the windshield banners of every Porsche Carerra Cup car racing this weekend. That fuel yielded the best mileage of the trip, 33.5 mpg while the rest of the averages brought the total down.

mazda mx-5 miata canadian road trip search for petro-canada ultra 94 fuel in ontario 6

9.760 gallons  – started out with a full tank in NJ
7.779 gallons 255.4 miles / 7.779 = 32.83 mpg fill up in NY
7.174 gallons  232.0 miles / 7.174 = 32.34 mpg fill up in ON
3.943 gallons 179.5 miles fill up in ON
7.595 gallons 207.1 miles fill up in NY
386.6 miles  / 11.538 gallons = 33.51mpg combined ON+NY
8.634 gallons 281.3 miles / 8.634 = 32.58mpg – last fill up in NJ
——— average 32.815 mpg —–

Why was this fuel mileage much lower (by 2 to 3 mpg’s) than the trip to Florida? Because the road terrain going up to Canada takes me via the Catskills and Appalachian mountains, and it wasn’t uncommon for the car to downshift just to negotiate some of the steeper hills along the way. The most flat road was in Canada following lake Ontario.

I am very pleased with this gas mileage. The car has just hit 45,000 miles total. I am running Pennzoil Platinum full synthetic which has just hit 3,000 miles, I will run it for about another 5,000 miles before changing to the winter blend 0W-20 vs. 5W-20.

speedway premium gas comparison to bp ultimate

While generally speaking I stuck to the highway most of the time, keeping it at or just above the local posted speed limit between 60 and 75mph in US and 100 to 110 km/h in Canada… I did deviate a few times to get food… like this highly recommended stop at Heid’s of Liverpool near Syracuse to pick up a couple of hot dogs for the road. They were delicious!

heid's hot dogs syracuse miata mx-5 road trip