Turbo efficiency definitely affects fe. Especially on a full size truck where you will be in boost a lot, whether you like it or not, just specifically because of the weight of the vehicle.
[Edit]: Back when I had my 2016 civic, I noted noticeably better fe in town if I rolled into 1-2lbs of boost while getting up to speed. Mainly because the car ran 14.7 until 4lbs where it would start to richen up. Benefits of DI.
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