[gemery]

If you begin to mod the car, you can kiss 30mpg goodbye.

Depends on the level of modding, driving style, and whether there are hills. Driving Pepper back from Nebraska to the Oregon coast, I got 30 mpg at speed limit to speed limit +5 mph. Intercooler & AdaptX tune, premium fuel (92 in Oregon, 91 outside of Oregon), and 245 tires.

 

[gemery]

Makes sense for those mods. Stock turbo stock cams right?

do you still have the active grill shutters in?
Rear spoiler moding, wheel offset, ride height, and mudflaps / side skirts would also affect the factory mpg.

Yes, stock cams & AGS.

Wheel offset is +40 & ride height -1" with 11k/15k springs F/R. Street Touring class autox rules don't allow aero mods, so no splitter/side skirts/rear spoiler mods.