Adam said:
Thanks for the responses.
Is there anything I can do in terms of aftermarket modification (in
addition to driving conservatively) that will increase the cars MPG?
Thanks.
Nothing that won't make the engine burn hotter (and not last as long.)
However, if you don't really care about a 15+ or 20+ year lifespan of the
car, look into Cobb tuning & engine management systems. They can override
the default maps and run the engine leaner (less gas, more air.) This helps
MPG somewhat.
On the other hand, on my bone-stock '04 STi, I was able to get what I
estimated to be about 560KM out of my 60 liter tank. Using US gallons,
that's about 35-37MPG. Of course, I basically coasted down hills, didn't
take the car above 110kph (~70mph), tucked the side mirrors in, turned off
*all* electronics and even the inside air fan, kept the outside lights
turned off and the inside gauges turned down low. I accelerated like a
slug, didn't accelerate when climbing hills, and I washed it like a
perfectionist before I started out. I kept RPMs when shifting below 2K, and
kept it basically in 6th the whole time.
The drawbacks: there were two adults and about 300+ lbs of gear in the trunk
and backseat, so I'm sure I could've done better. Plus that was with a mix
of 91 and 0.25 of a tank of 94 and some octane booster. Full, clean 94 AKI
would've probably gotten me another 20-30KM.
It was too hot outside to be playing those kinds of games.. the person I was
with at the time didn't particular like me doing that, sweating inside that
little hotbox of a car on a nasty, muggy summer day.