Im a few hours away in Edmonton and my car is fairly similar. I get probably around 350 to a tank, but right now its kinda sucking back the gas in the cold so probably about 320-330. I find that in the city the mileage isnt the hottest, but it does pretty good on the highway. It might be a bit better than that but i also like hearing the secondaries open up so that doesnt help much.

1997 Mercury Mystique -Tinted, Debadged, and no more door ding guards -Dual Exhaust With Magnaflow Mufflers -Gutted Precats -SVT rear sway bar w/ES bushings