So my 2002 SE/SC gets horrible gas mileage, that's not secret.
On average, over a two year period, driving with a light foot, I'll get 210 miles per tank - sometimes a little more, sometimes a little less.

I chase fires for a living (photographer) and use the city vehicle so I don't beat up my personal vehicle. Well, this week the city vehicle was in for repairs, so I used my Xterra.

With HEAVY driving all week (think hard acceleration most of the time, hard cornering, and hard braking) I am now on 220 miles for the tank. Get this....I still have 1/4 tank left!!

WTF???

I read in Road & Track some time ago that most engines are designed to be most economical if 3/4 throttle is used during acceleration. I didn't believe it, but now I am changing my tune.

I am baffled.

I always heard the old timers say that a lot of the 4 barrel carbs would get better mileage on the highway when going 70+ but I've never heard anyone have that big of a difference (not that the X has a carb but u get the gist). Pretty impressive.

So will you get to drive the X more often now?

...and what's weirder is that you should be getting WORSE mileage than ever before thanks to the ethanol they're watering down our gas with now.

I think the actual reasoning is that engines are most efficient at or near wide open throttle. But efficiency in this case is defined as producing the most power for the amount of gas being utilized. For the most part, a vehicle does not need max horsepower (cruising down the highway at a steady state 70 mph, for example).

Does the S/C have variable valve timing?? I had a BMW 325Ci and it got about 5 more miles per gallon at 80 than at 55 mph because over 3200 RPM the var. valve time kicked in and the engine got to breath better. That might be true with the X as well

Dunno. It is completely stock (well, sort of. I have a K&N filter in the factor air boc and a Magnaflow muffler)

All I can think is that I need to drive more aggressively around town on a regular basis.