91 or 93 Octane

[sixcrows]

Originally Posted by gusfraga

I can get these mpg not even close.
Are you an hypermilinng guy?
Gus

Those numbers aren't typical for me, Gus.
I am averaging almost exactly 41 mpg.

The 57 mpg measurement came on a half tank of gas, and I'm guessing there were optimal driving conditions for that half tank.

I'm not a hypermiler, but I almost never exceed the speed limit, I pull away from stop signs and red lights at a crawl, and I try to maintain constant speeds, avoiding breaking and re-acceleration whenever I can. Hypermiling techniques, certainly, but I don't do the extreme stuff like shutting off the engine when going down hills.

[MPrice2984]

Just out of curiosity I looked at the CR's of all the US Mitsubishi engines and what fuels they recommend. For the 10:1 cars Mitsu recommends mid grade 89 octane. I talked to my local Mitsu tech and he said 91-93 is a waste. I switched from 93 to 89 and my mileage went up from 41mpg to 43.7mpg. Guess what, no pinging and no loss of performance either. Other Mercedes techs I've talked to say that most Mercedes operate fine on lower grade 89, Mercedes likes 91-93 because of the extra additives. Since I use a bottle of Techron about once a month that does the same thing.

[HGB]

To keep all those 71 horsies happy feed the engine with the best.