No boost = 17-18 MPG on interstate cruise control @75MPH. Not much less taking her easy in town.

Boosting often to jostle for position or to get away from a congested pack and cruising when I could @ 90MPH and some higher short sprints and taking on a few challenges on a road trip of 500 miles from above Atlanta to Tampa = 13 MPG AVG.

 

I got 10mpg with 50/50 e85/91 the past couple days with mixed driving and beating the hell out of it pretty regularly. Had it up at 19psi last night, so it was consuming some fuel. I don't think that's too bad considering how hard I've been driving it lately.

 

That's not bad at all. If you went to 100% e85 I bet it would drop off significantly though.

 

That's why I made the switch to 50%. 100% e85 mileage was just horrible.

 

I'm halfway thru a tank and based on mileage I'm estimating about 6 mpg. Granted I've been playing around but still...

 

Still about 19 on the Duramax, 21 @65mph on the 07 sts when I had it. Still though the Zo6 would get 29-31 on a cruise. It wasn't boosted but ran it *** off and looked great doing it. It would beat the 07 on the road just not in a drag race. Think I'm gonna get another one in the near future.

 

19-20MPG on the hwy if I leave it at 65MPH with cruise control. Usually someone want's to play though and that millage doesn't last.


City driving and playing in boost a lot I am 12-13. If I drive like a bat out of hell 10....

 

I got a new tune from Justin at Black Bear and went from 13.5 to 17.8 on Premium.
I noticed the truck wasn't loading up like it used to with the richer mix.
The response is tighter now.
I'm going to run it a few days and send him another log and we'll tweak some more.

 

Got my final tune for this year and rounds of mods from new era today.

Drove there getting 17.5 which is pretty good.

Coming home I got 20.4!!!

Both drives were the same distance and cruise at 70 mph.

 

Damn I wish I was getting your guys' mileage. 2011 2500 Burb,L96,TVS1900@10psi,3.73, 33's on 20's I'm at 10-11 city and 13-14 highway usually @75-80mph.
My 2001 2500HD CC with 8.1, Whipple 2.3,3.73, 37's I get the same in town as the burb and 13.5-15 on the highway.