:whs: I never saw an improvement in mileage with my Aeromotive pump.... nor did I expect one. Unless your HPFP was starving (which will cause a lot more problems than poor gas mileage) or the factory LP was sucking some serious amperage compared to an Aeromotive, I don't see how this would be possible.
OP, are you sure you didn't change anything else when you did the pump?
I just filled up the tank all the way through the filler neck to the top to be consistent. Did that before the pump install and have done the same thing since having the pump to compare numbers. This pickup only sees highway time too, I'm sure that helps.
I've never taken my H&S off "mild" since I've had it either (or ever for that matter, I'm a boring driver)
Jared at Aero asked me test the pump, and if someone asks you test a free pump they install, and share the results with him and the forum you lurk on, I'm sure most everyone would do the same. Plus, it got me a very nice tour of the shop and toys there. All I'm doing is sharing my numbers. Is what it is I guess. I'm enjoying the difference.