Originally posted by DakarM
most combustion engine is not the most efficient at idle or just off idle.
with the M coupe I get 26-27mph when i'm cruising at 80-85mph on the freeway. if i slow to 70-75mph the mpg stays the same or drops by 1mpg.
80-85mph ~ 3400rpm in my car
I try to keep mine at 2500... friend of mine thinks its good for his car if he keeps it at 1000. This is the guy who already shot the transmission on his C5 once already.