Originally Posted by bulla

I was thinking today while driving to church, what setting on my DP should make the best milage. I'm not talking in town, or back and forth to work on the interstate. I mean with the cruise set going down the highway! You would think it would be the same but how can it ? In one setting my boost is higher crusing than the other, so wouldn't the one with the higher boost burn more fuel?

Originally Posted by DP-Tuner

Yes low boost on the highway is the best for mileage and is why we came ot with the 60hp econo tune. This is also why I run the GQSSB turbo on my Excursion. This is a very efficient turbo and normally runs at 2 psi on the highway which helped me to get 21 MPG with all of my mods. The higher the boost the more backpressure which makes the motor work harder to maintain the speed and causes a loss in mileage. This is another reason I do not recommend the GTP38R turbo.

Jody

Originally Posted by F350-6

Here's what some guy named Jody says about that.