Exhaust Mod: Keeping the CATs and Cutting the Muffler
 

Hey all,

My first truck (RIP) I got a cat back dual setup from the local O'Rielly's, which cost me over $400. It was a 03 5.4L V8.

My new truck is a 06 5.4L V8. It has twin CATs which join into a Y pipe that goes out to the muffler. When I was installing the dual system on the old truck, after I removed the muffler I started it to see how loud it was. It wasn't any louder than after I had the dual system on.

My question is this, if I chop the muffler off the current truck and just extend the pipe out the back, will that negatively effect the truck at all?

I know that the CATs will create plenty of back pressure, so I am not concerned about that. Would there be any benefit to go from the stock pipe size (I think its 2.5, have not checked yet) to a 3" pipe (from the CATs to the back). My dad is telling me this will make it flow better but he doesn't have any exhaust experience so I am a little suspicious.

Thoughts and suggestions are appreciated! Thanks!
-Nathan

Some say it'll create back pressure problems, some say it won't.

You will have no benefit increasing the exhaust pipe to 3" on a stock, normally aspirated 5.4.

It really wont do anything negative or positive to the truck. Just carry the sound out the back of the truck. Without the pipe the sound will just be right under the rear seat.

Ok so if going from 2.5" to 3" doesn't have any effect, what benefit is the dual exhaust kits? Unless they are true duals, are they pointless?

Will creat backers sure it's due making a light come on. I installed a one chamber muffler and a code comes on about not enough back pressure. I want to do a 3.5 cat back because it will give it more rumble because my buddy had 3.5 and it gave it a deeper tone and more loud sound.

Same goes for a single in dual out muffler or true duals. You won't notice any performance differences on your truck. You'll only notice that it's louder.

If it was highly modified and not N/A I would say go for it. But right now it would be a waste of money. Unless you're after more noise.

Would it make any difference if there is a air intake mod installed?

Hmm, I wonder if a smaller diameter would eliminate that issue.

You already have one.

LOL, here we go again, I agree with you but some people just don't get it.