Has anyone done a study on the diff. in MPG using the 87 or 93 octane gasoline? I'd be interseted to know if an increase in MPG while towing could offset the price difference.

Teach

FWIW I have tried both in dragstrip passes and there was no difference....not even a tenth.

As an experiment I switched to high octane for a this summer's camping trip to PEI while towing 5800 lbs of travel trailer - no difference in performance or economy.

I have never recorded any increase in fuel economy when switching from 87 octane to 92. I have, however, recorded a slight initial improvement when switching to Shell V-Power right after I bought the truck but I attribute this to the better quality detergents cleaning up the injectors. My opinion is that this process would be better (and more efficiently) served through the use of a quality fuel injector cleaner.

It is my understanding that higher octane is only necessary with higher compression engines to prevent pre-detonation. Perhaps another member with more knowledge will chime in and educate us?

I worked for Napa Auto Parts years ago. I have always used Mac's 6660 fuel injector and intake cleaner. Shake well and run with atleast a 1/2 tank of gas. Really good stuff. I run a bottle through every 5,000 miles.
As far as higher octane, you have to run more than one tank to see a difference. Don't expect alot. I tried it on my Tacoma while towing, and the mpg didn't offset the difference in price.

NM doesn't mandate minimum octane as other states do. I run mid grade (usually 88 octane) and see about 18.5 in the highway. I have always run mid grade since every engine I have owned requires 87 or higher. I only ran 91 or higher in my Ford with the programmer on. I have 2 other Tundras at work (Father in Law and a co-worker) and the one (father in law) has indicated that he gets better mileage with mid grade, the other, even though it is a 2011 with 8K on it, gets crap for mileage running 86 octane.

My fatehr in law and I both average 17+ and the 2011 sees about 16 average.

You'll see a difference from fuels containing ethanol (10%) to switching to a high octane (not suppose to contain ethanol). Other than that on N/A engine you will not notice a difference but it WILL run better and produce slightly more power.