Post your stock TC mpg and what octane fuel was used. The most I have gotten from my tc was 27.5. I average 26-27. I haven't gotten to bad gas milage except 1st tank which was 22. Since I have gotten at or around 26-27.

 

So far I've got 24.5 and 25.5 on my first two tanks. Lots of highway driving to work, however I do have a heavy foot.

 

100% city tank was 21-22mpg..best 100% highway was 27mpg...auto w/5,000 miles all on 87 octane.

 

my mileage was before the k&n air filter. Mixed octane. 87,89, and 93

 

why would u mix them? just find a midgrade

 

Anything higher than the recommended 87 is a waste of money.

 

It is recommended to only use 87 but you can add a tank of 93 or better once in a while to keep the injectors clean.

 

That's only true if you buy crappy gas. Most reputable stations (at least here) include detergents in all octanes. If you buy from somewhere shady you might need to buy high octane to get detergent in it, but the detergent is what cleans the injectors, it being higher octane does nothing.

See here:

http://www.state.mn.us/cgi-bin/porta...gency=Commerce

 

If you read the owners manual it said the research octane is 91. This is the octane that was used to determine the mpg, hp, and tq.

 

"If you read the owners manual it said the research octane is 91. This is the octane that was used to determine the mpg, hp, and tq."

What page? I can't find it. Besides, I thought the EPA determined the MPG rating, not scion.

 

This is interesting...I'm going to look for this...

 

http://pressroom.toyota.com/presstxt...005tC_tech.pdf

See page 13

"engine output on regular 87 octane"

 

The date on that is April 28 2004, My car was made Oct 04. I am not sure what date the owners manual says, but in the owners manual it said research octane was 91 or higher. Read it! Both articles contradict one another.

 

RON = Research Octane Number
MON = Motor Octane Number.. divided by 2 is what the pump octane is.. have to determine what the Motor Octane Number required for the tC is.. then the pump (what you get at the gas station) octane will be known.. i calculate 91 RON and 83 MON (was pre-selected in the calculator I found) and got 87 Pump Octane (found a calculator for this online)..

I also found this from Shell of Canda.. guess the American Shell doesn't care to educate the american consumer.. anyway here is the definition of RON and MON from Shell canada..

http://www.shell.ca/code/motoring/tips/gasoline.html

 

Thanks for clearing that up. I got a little mixed up. When they said research octane I just thought that meant that they used 91 when they tested it.