i have pacesetter shorty headers with no cat going to a qtp e-cutout then to a flowmaster super 10 basically straight pipe from headers to cutout. might be loud but does **** for performance. truck is slow as dirt with the cutout open but when closed going to to muffler big difference. so if your thinking straight pipes all the way back and still want performace think again! ya its loud really really loud. but will hurt you in a drag or 1/4 mile! anyone else experiment with this?

 

So you're saying that with the cutouts open it's slower?

 

I tried that before, the truck needs the backpressure, runs like a bag of ****e without, plus burns a lot more gas i found

 

Ya when I had my cutout I noticed the same . Install a highflow cat makes a better sound and I had more power also