My gear ratio stinks (will larger diameter tires help?)

[SilentMatt]

I've played with the calculators, should drop my rpm down to around 2900. My wife has taller tires on her Aerio, and she only does city driving, maybe I'll swap her and see if it helps.

[MetroMPG]

I wonder if anyone has cross referenced the Aveo manual trans to see if it was used in other cars with more powerful engines. The trans with more powerful engine would usually have different (taller) gearing and might be worth investigating for a swap.

Depending on how far you want to go with this.

[SilentMatt]

If my clutch were on the way out, I might think about it. As of now though, I'm not willing to sacrifice my weekend tearing into it. Would still be interesting to see if any other cars used it though. Maybe one of the Opel cars?

[Melveo]

Gearing is about right. I'm at 3k at 70 . Tires have a tiny bit to do with it. I'm slammed on 18s and was still get 35+mpg highway cruising at 70. But hauling ass on the highway drinks the gas, to at one point I was burning half a tank every 100 miles doing 80+, but not anymore since I'm maxed out. I get great gas mileage now🙃😂

[MetroMPG]

Good point about speed, Melveo.

At highway speeds, the vast majority of fuel is burned to overcome aero drag.

http://www.aveoforum.com/forum/f106/...tomatic-13851/

A few simple & cheap aero mods would probably save more fuel than changing tire size or gearing.

Or just slowing down some.

[06T200]

The best I could get in my LS was 31mpg, and that was with a heads up display of the current mpg while driving. The gauge seemed to promote right foot discipline. Since I have taken the live mpg display out, I average more around 23mpg now. But I can get home form work in about 7 minutes.

[Melveo]

The best I could get in my LS was 31mpg, and that was with a heads up display of the current mpg while driving. The gauge seemed to promote right foot discipline. Since I have taken the live mpg display out, I average more around 23mpg now. But I can get home form work in about 7 minutes.

how did you install that

[06T200]

how did you install that

It plugs into the OBDII port.

Here is a picture of it in action: http://www.aveoforum.com/forum/f108/...ping-up-16771/

[SilentMatt]

Yes, I'm sure if I drove 55 I'd get great mileage(and get run over by the truck doing 65-70). The fuel going into the engine is dictated by the amount of air going into the engine, so I think any drop in rpm would be helpful. I know the best way to save fuel is to change the way you drive, but I'm trying to get the best mileage possible with the way I drive.

[petrified.rabbit]

Im don't usually bother getting involved in the best MPG threads. But, your aveo must be a 2009? and a manual? I only say that because the 2009 had a tighter gear ratio than the 2010-2011. Its marginal, but i think it was about a 300 rpm drop at 60mph?. They changed the ratio for the US emission mpg requirement change.

I *think* it might have changed twice, again between 2010 and 2011. But I am not entirely sure what the ratios became each time. It might have been @ 300 rpm after both transitions.