Thanks for the replies everyone.
MetroMPG: That's pretty impressive. I had no idea that the Grand Ams were capable of that.
In general, it cruises along at 25-27MPH in 4th gear, and 35MPH in 5th, just barely above idle.
MetroMPG: For a few years GM liked to put excessively rounded transitions on the trailing edge of their trunk lids. I remember reading an article about how adding a spoiler to that style of trunk lid reduces both drag and lift.
Makes sense to me!
Radioranger: Just checking out your picture and the license plat could probably be a partial lower grille block
Except the license plate mount is horribly loose. It's on my list of things to fix lol
Mcrews: Dont forget to increase the psi to 40+.
Also, I bet you have room to increase the tire size on the stock rim.
There are several threads where this is discussed (successfully)
The KwikTrip gas station on the corner has a weak air hose, took a long time to get all four up to 37ish PSI. It currently has 195/65 15"s all around, any suggestions?
One lingering thought I've had is to do a full foam and fiberglass body kit. The nose would resemble the late-90s Firebirds with a smooth round surface. For the sides, the stock body cladding would be extended vertically straight down so that instead of the car tapering in towards the bottom, the sides would be completely flat. Then some Basjoos front skirts, similar on the rear, working with the belly pan... Would the effort be paid back? It would completely smooth the flow around the sides, wheel wells, etc. Any thoughts?