Originally Posted by
George Knighton
I have a 2006 6-6 HFP Coupe.
I will get 30 miles per gallon on 93 octane BP. It has gone as high as 32 mpg.
The car performs really very well and there really isn't a lot I can complain about.
There is also a 2006 6-6 Sedan in the family. It seems to get 26-28 mpg on 89 octane BP and won't go better than that. I guess it has to do with the extra weight it carries compared to the Coupe.
I had no idea you had a 6MT, George...
I haven't noticed any difference in fuel economy related to octane rating. My best tanks of 33-34 were all with 87 octane BP. I've noticed that 6MT gas mileage is highly dependant on the driver...some people get high teens in the city, I usually get mid 20's. I don't have the navi/trip computer but I did some testing and figured out that I average 34MPG doing 65 and 31MPG doing 80 (it's pretty linear for the speeds inbetween) so engine speed isn't that big of a factor esp compared to my old 6th gen AV6 which got 26MPG at 80 :chuckles: