dk@[EMAIL PROTECTED] (DK) Aug 25, 2008 at 05:16 PM wrote:

>Impreza 1993, EJ18 engine, manual.

>Exclusively city driving, average trip about 5-7 miles. Was trying to
>drive keeping RPMs close to 2,000 or to 3,000. For the most part
>in practice it meant choice between 4th and 3rd gear.

>Same pump, fuel contains "up to" 10% ethanol, same weather, two
>full tanks for each "condition". The milage was consistent between
>two tanks in each case within 0.3 MPG. Results:

>~ 1,800-2,300 RPM = 26.7 MPG
>~ 2,500-3,200 RPM = 28.1 MPG
>(No, EJ18 is not a marvel of fuel economy :-))

>Based on what I read before, I expected the opposite result. In any
>case, the difference is no more than 5%, so it's not really worth
>it to keep attention to. Lower RPM is less noise and less power.
>What's better for the engine in the long run?

>DK

Longer trips will do the most to increase your engine life and minimise
wear! Most engine damage occurs in the first few miles/Kms when the engine
is not properly warmed up. If you run a longer distance for your test, you
may notice more variety in your figures. Cheers

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