I was thinking about building a 50 MPG 02 with a motor from an 84-85 318i, or possibly an m42 with a 5 speed overdrive, AC, dark tinted rear windows, a comftorable interior (newer seats) and a good stereo, any ideas? I would use a low gear ratio to turn 2000 rpm at 70 or 80 MPH, areo mods, and makew the engine as efficent as possible...