Just want to see if I would lose a lot of power straight piping the 4.7, I mean the power it has might as well be a 4 banger. I tried doing it already but gave up. Got a flowmaster 40 series on there now, the inlet is stuck to the pipe off the cat. The clank came off and the pipe moved up and down but I couldn't pull it out, am I missing something? I'd like to keep the muffler to use for inspection

 

I think strait pipes are generally only good for noise, not performance. The lack of back pressure is something the motor wasn't designed for.

And if I read the second part of your post right, it sounds like you are having issues getting the muffler off the pipe? It sounds like the clamp just indented the pipes on to each other. When it happened to me, I ended up just cutting the pipe with a hacksaw.

 

I don't tow a lot so it's no big deal for power, and that's definitely what happen on the pipe from the cat to the muffler but the pipe on the cat moves freely up and down, you know of any way to somehow loosen it up to pull it off?

 

Not really. Like I said I just cut mine off. Maybe careful heat, enough to expand the outside pipe but not the inside pipe. It won't give you a lot of extra clearance, but it might be just enough