Which grade of Gasoline provides the best fuel economy? - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

dirtytaco · 10-15-2006, 21:24

Obviously driving sensibly helps the most, but i feel that i just can't drive more sensibly. I have it dialed in. I always maintain momentum, drive 55 on the highways, and anticipate red lights. My car is always kept up on maintenance. I also have a k&n.

Now on to the gasoline.-since i got the car on june 29th, i've gas'd up 3 times. Each time at shell, each time filling it up with premium.

(1989 Ford Probe LX 2.2l Automatic)

Right now, the fuel mpg light indicator shows 7.7 Liters/100km, which on one site converted to a little over 30mpg.

The way i drive, i think it's possible.

But my question is, how heavily does fuel grade influence fuel economy? I have no problem paying extra for the 91 octane shell vpower. Especially if it's better for my car.

Here in Nebraska, there a 3 main grades, Plus (87) Regular (89)
and Premium (91)

Obviously i want the grade that's best for my car, and one that helps the fuel economy.

I am a little wary of the 89 grade because it has 10% ethanol.

Any help guys? THanks.

ZC-Cruiser · 10-16-2006, 23:49

I like the 10% Ethanol - seems to make the Fairlane run cooler, more power, less pinging and better fuel economy...

Ethanol is an excellent Octane Booster and at a 10% concentration, unlikely to cause any damage to a modern car.
In fact, since Ethanol is very hygroscopic, it will absorb the moisture from your fuel tank and help prevent rust in there.

Dr. Disque · 10-17-2006, 11:17

the best grade for your car if your car is stock or close to stock is the one recommended by your owner's manual

dirtytaco · 10-17-2006, 11:30

i'll have to take a look in there. Yeah, in the winter time, i guess ethanol wouldn't be a bad idea because it will keep shit from freezing. Right now, i'm maintaining a steady 7.7L/100km (my 1989 Probe has an electronic indicator) so that's slightly over 30mpg according to conversion sites.

I will say, the probe has some incredible technology for being an 89.