All of the gas stations claim higher mileage with the "premium" level of gas. Has anyone tested this on the prius and noticed a difference at all? How about Shell's new "premium" (sorry, drawing a blank on its name) gas that claims a much higher MPG and much cleaner/lessened emmisions? Jeremy
I think someone did a test with a classic (1 - 2 mpg boost??) but do now know of anyone doing this with a P2g.. I think the mpg boost would be only 1 maybe 2 mpg.. not worth the $$$ and cleaner/lessened emmissions... only because it has a fuel system cleaner built in the "V" in the tank... I just ran the Chevron Techron (sp?) through two tanks to clean my system... kinda pricey but time will tell if it does any good ( time as in 80,000 miles plus on the car)... just like using Mobil 1 oil...time will tell... later
I tested higher octance with my Classic. The results were the same as Toyota's documentation stated: it is a complete waste of money. The engine is Prius is specifically tuned for low octane (87 normal, 85 high-altitude). So higher octane has the potential of actually making MPG worse, not better. It also has the potential of triggering an engine warning light.
I don't know about Shell's (is it V2?), but generally speaking, using a higher octane gas than recommended for your car not only doesn't improve mileage, it can increase emmisions.
That was not true formy Dodge Omni, ages ago. But then again, those were the carburetor days. There was a definite MPG improvement with higher octane.
85 octane works great here in Colorado. The Atkinson cycle likely eliminates any risk of pinging or knocking as well. Nate
Using a higher than necessary octane will decrease fuel economy but what has been your experience regarding power? I again offer this web site as documentation that higher octane fuel will increase power in a prius. http://www.creedproject.org/stream_v7n2.pdf (page10). More power facilitates smaller engine for same acceleration which could improve fuel economy IF the engine was bi fuel using high octane for acceleration and low octane for cruise
I run Mohawk Ethanol Plus 90 octane here in Canada. It's the only way I know of avoiding MMT in the gas. So far my fuel economy is in line with what everybody else is getting, and the motor runs well. When I drive in the United States, I fill with the cheapest 87 I can find, from a major retailer (BP, Conoco, Chevron, etc). I don't have to worry about MMT driving in the U.S.
For those of us in USA can you tell us what MMT is? Is octane in Canada the same as octane in USA? There are so many variations in terminology and regional variations in fuel additives. Sometimes these factors skew the objectivity of some of our comparisons. Is there a significant change in your mileage when you use Canadian gas as compared to US gas?
MMT = Methylcyclopentadienyl Manganese Tricarbonyl. It's an anti-knock additive developed by the Ethyl Corp but it's banned in Europe and the U.S. The big problem with MMT is the manganese, which damages emission control components and also creates manganese in the environment. As far as octane ratings, they are supposed to be similar. The mileage can decrease when you run Canadian gasoline with MMT, especially in city-cycle driving.
