Hey I am in the process of swapping a 2016 5.0 into my 97 F-150. I am almost done with the build but I can't decide where to put my cutouts on my exhaust. I have long tube headers and two 3" electronic butterflyutterfly valve cutouts that I'm going to install so my truck can be silent at home but loud on a late night drive. I've been hearing conflicting opinions on the safety of putting cutouts right after the headers. The main thing is that cold air can rush back in and burn a valve on shutdown. However if I make sure I don't have them open on shutdown I should be fine right? If I don't put them after the headers then I'll put them after the cats, but that will take some more fabrication to fit. Have you guys done anything like this and if so how is it working out?
Thank you.

 

Not very many people have installed cutouts. Are you going to use a dual exhaust? With an X-mid pipe or H-mid pipe? If so, I've read you should install the cutouts 'after' the X or H mid pipe. You know, before the mufflers Just from what I have read

 

To avoid the potential for problems, at or after the crossover pipe is ideal. Before it, not only do you lose performance but, you have the potential to get the burnt exhaust valves or even a backfire from lack of scavangeing effect.