[Big Dave]

My bad! BBHP is out of business but there is an outfit called F2B that makes a T-56 swap kit.

The Impala SS Forum is an excellent source of B-Body info. They helped me out with a bad digital odometer. Their fix saved me $400.

I just picked up an Impala SS (always wanted one) to drive while I mess with the truck. Excellent car! Roomy, fast and durable. B-Bodies are favorites to export to the Sandbox. They are favored for their solid suspension (able to take the rough roads) and killer A/C. Just posted my first run. I can see they are not city cars but my driving is only 35% city.

I drooled over the idea of ecomodding a ‘Vette, but the harsh reality is that you can tear a ‘Vette all to pieces and still command a price over $10,000. Tango Charlie got a pretty good-looking wagon for $2500. Now that is in the range for a project car. If you started with a tatty wagon, executing bbjsw10’s little distortion is not impossible.
Let’s think on that.

It looks like there is about 40 inches behind the C-pillar. If you have a clunker to start with (you don’t feel bad about starting with an application of the ol’ emergency grinder) you start by narrowing the tailgate by 16 inches. Narrowing it 8 inches per side is an 11 degree taper. Likewise lower the tailgate by 8 inches (holding the 11 degree taper), and maybe raise the bumper by 3 inches with a diffuser and you have reduced the wake area by 41%.

Since I haul more stuff than people, I could go more radical. Weld the back doors shut and make my breakers at the B-pillar. Now I have 60 inches to work with. I could hold my 11 degree angle (a 1-in-5 slope is 11.3 degrees) and narrow the car 12 inches on each side and 12 inches down. Assuming a 3 inch diffuser, that is a rear wake area reduction of 56%. With this setup, one would probably have to put a narrowed rear axle and relocated the wheelhouses inward a bit. This much what the old Insight did.

These cars offer a lot of scope for other aero mods.

In either case, a suitable diesel engine and a T-56 along with a 2.73 ratio would put you into drivetrain nirvana.

I think 45 MPG is doable.