He's coming from a tuned EB 11 so keep that in mind. He's a little disappointed at the feeling of lack of torque down low. Remember, a tuned EB f150 does about 515 rwtq and the whipple is rated at 440ish (reading graph, so can't be exact) torque. That's easily explainable. But he does say that it pulls good at top but hasn't played much yet. Fwiw, whipple rates at 525 rwhp and tuned EB made 370 rwhp. So, it'll feel slower down low due to both less torque and less peakyness (much flatter curve) than the EB but should pull like a raped ape compared to the EB. I had actually warned him about that.
Yes, Dustin told me the kit for the F150 is not as powerful as the Mustang. It's just the wrtq difference that he's noticing. My last truck was a 2012 ecoboost and after the down pipe, Wagner inter cooler, AFE stage 2 cold air, solo performance catted Y pipe, solo exhaust and VMP tune my truck was insane. I never dyno'd it but it was crazy how powerful it was.
The F150 is a bit more conservative when compared to the Mustang because one can tow with the F150. We can make 515RWHP but if you tow with it, then its closer to steady state and you have a lot more issues. Same with the EB, you can make great power but playing with fire under load conditions.
The can always put the 3.75" pulley on vs the 3.875" but its not as ideal for towing. Makes about 30rwtrq more though.