I have a 2005 1500 4x4 hemi and I am looking at putting some aftermarket parts in it. Dual exhaust and cai. I have been looking at different exhaust and allot of what I found is just a mufflr with 2 exhaust ports and pipe straight back out the bumper. are these any good? I havent had anything to do with exhaust in a few years, I remember going straight off the Y and running 2 mufflers and everything, what has changed?

Does dual exhaust and a CAI make a difference?

 

A lot of it is going to bolt on's, so they mostly follow the factory stuff so you can use the existing hangers. But there are still plenty of different things you can do. I added long tube headers, so I had to cut out from the manifold to behind the cats. Moved the cats back about a foot and a half to accomodate the headers, lengthened the O2 sensor wires and pretty much went true dual till the muffler. Muffler is a Flowmaster 50HD, 2-in 2-out, so it pretty much is also my "H pipe", then back out to a tail at each side of the back.
For true dual, I coulda just put two conventional mufflers "back to back", but I've always believed there should be a "Y" or "H" joining them at some point. Don't know if it's that critical, but it's the way I was taught as a teen...

As far as making a difference, the 3 most popular mods are: exhaust, CAI & tuner. In that order...

 

I have a magnaflow muffler on mine. 3inch inand dual2.5 inch out. For little expense i got the nice looks of stainless tips out the rear and nice sound...i guess to me it would really depend on what you want out of it. Just the look and sound or real performance.