[Ladogaboy]

So I've already done the two major mods I'd planned to do for economy (LRR tires and ECU retune). The tires have netted me close to 10% increase in mpg. It's too soon to tell for the retune, but I seem to have gained another 7% or so (the AFR was leaned out from ~10:1 to almost 12:1). I still need to crack the map and advance the timing in a few areas, but otherwise, that's done.

I have a number of ways I can go, but I'm thinking aerodynamics or rolling resistance might be next. One thing that got me thinking is that, on a downhill freeway slope, my car will slow to less than 60 mph with no throttle. The way I look at it (possibly flawed thinking), that means that even on flat road, my car takes more energy than gravity to overcome its drag and rolling resistance alone at 60 mph. That seems to be a lot of energy, and I'm weighing my options for how to lessen it.

Two things to consider: My car's Cd = ~.33, and it's an AWD (which I'm guessing does me no favors in terms of rolling resistance).

Anyway, suggestions on where to go next (budget minded, ideally) would be greatly appreciated.