Quite a bit according to this thread.

Doesn't surprise me, the intercooler is there to help the efficiency of the turbo by cooling the air. Blocking off sections of the intercooler with a deflector is insane. You are defeating the intercooler by blocking it off, and making the turbos less efficient, producing less horsepower and torque.

Ford is really opening themselves up since the fix provides less power than the vehicles was marketed and sold to provide.

I still feel he 6.2L is the best engine to buy for towing.