27mpg...average. $20 at 2.69per gallon...7.4 gallons...just around 200miles per half tank. (do the math, I am weird about filling half everyweek since that is what is needed and aids in keeping the deadweight down to a minumum for me)
New O2 sensor, cap and rotor are yearly. I replace these every 3 months...new air/fuel/oil filters, I replace these every 6 months...new plugs (ngk platinum) and flush the radiator, calipers are good and brake pads are replaced every 4 months (autozone warranty for their best brakes and about an hour of work). This is on the daily driver S14, with just a 3in. catback, removed resonator on the intake box, a religiously cleaned TB and MAFs, still have awesome compression as well. Also maintain consistent speeds (ocassionally burst when entering the highway), use the AC on the highway, always wash and wax the car weekly, and regularly clean the engine bay the keep trapped heat down to a minimum and let the block do what it was designed to do as far as the exterior was designed to do. Tire levels are perfect, and have nothing extra in the car. I do all this because it is my work car and deserves at least that since if not for it, I would not have a job.
On another note, I was getting a miniscule increase at around .25 to .5 mpg increase when removing the passenger seat, spare tire and jack, and sub box consistently (total weight of around 130lbs), but didn't see any point at the expense of piece of mind and enhanced tunes.
