Greetings,
I've been testing some aero mods -- using good old duct tape, for the moment.
Simple stuff so far, and it seems to be quite effective: my best tankful average last year was 41.8mpg, and with some improved driving techniques, I got 43.5mpg on a tank. After covering the upper grill, I've got a new best of 45.5mpg. Then I covered the fog light recesses, and it's looking much better still!
The 45.5mpg tank was ~239 miles at the half tank -- and this tank is sitting at ~275 miles at a half a tank left!
So if I do only 200 miles on the second half tank, that could be ~47.5mpg! Heck -- I might be on course to do almost 50mpg?! Incredible, if that's how it turns out.
[Edit: I ended up with 46.4mpg, partly because my last commute up Route 3/93/95 and on Route 117 was pretty clogged with stop and go traffic...]
So, I'm going to be trying to construct an even sleeker nose -- if I can form some planes to kick the air flow out and around the front wheels, and keep the required cooling (today was very hot -- near 100F and it worked fine!), then I could be exceeding what I thought this car was capable of.