That was completely the intention...I am willing to bet the truck even loses hp with them open all the way. I haven't taken it to the track after I installed it but I am willing to bet it runs the same or is slower now. Only mod to the truck is an altered air cleaner and a programar installed.
I have modified every exhaust system on all the vehicles I own from my bikes, 4 wheeler, cars, and trucks. Even track tested them so i have learned what truly works and what just makes a lot of noise... .