Some background. I have the 5.9,3.95 and I recently installed Tony's air intake with 1750 miles on the D.
I pull a boat & tandum trailer weighing out at about 6000 lbs. I took the boat in for service before I installed the air intake. To go from the coast where I live to town inland I havfe to pull some 12-15 degree hills and one short 19 degree hill to my home. The D pulled the boat in fine. I installed the air intake after the boat was in. It worked great. I immediately saw an improvement in mpg. My average before was 15.4 and my first tank with the quick D intake was 16.1. Being in a rural area, most of my driving is highway at 60-70 mph.
[QUESTION] When I pulled my boat home it didn't feel as if I had as much power as I did before the air intake was installed. I pull at 55-60 mph., and it seemed to need more throttle on the hills than I remember going in. (Could it be the wide open carb sound from the air intake) I have to work to get increased speed from 3200 rpm to 4200 rpm. Is this my imagination because I don't have a lot of experience pulling the boat with the D ? Any thoughts would be welcome