31 average (comfort mode 80% Hwy 20% city)
93 octane premium from Shell or BP
MPG calculation done with calculator - not on car computer which is about 5% optimistic
By the way - I tried 89 octane on 3 tanks. Lost about 4% mpg. Considering the 4% extra cost using 89 octane, 93 octane is about the same cost in the end.
2012 528i, Space Gray, Black Dakota/Dark Wood, Technology, Premium, Cold Weather, BMW Apps
2013 Porsche Cayenne
Last edited by FreqMan; 01-09-2013 at 04:46 PM.