FWIW, I've been averaging 25 to 26 with my '85...but I remember hearing that '85's had higher gearing than other turbos (most turbos have 3.07 rear gears; I think '85 have 2.??'s)...
I can't complain, but I have to admit that the '03 Jetta TDi that i drove yesterday did quite well for a vehicle that gets 45mpg on a bad day. No I'm not thinking about replacing the Benz; my mom wants a Jetta and I'm trying to convince her to go diesel...