[dremd]

Welcome.

with that low of a final drive the slower the better (down to like 30mph I'd guess)

Try and see if you can swap in a taller 5th out of something else.

Which transmission do you have? May be able to swap gaer from camry, or the likes.

I Owned a 91 GTS for a bit, it was a nice ride, mine was the newer body style, Loaded Power Seats, Automatic climate control, sunroof, 8 (or 10?) speaker sound system, factory spoiler, Nice rims from a later celica, the big brakes etc etc. I miss that car.

You can try headers/ port match, but I'm guessing that they will hurt not help mpg.

Check the stickys for starter mods.