A wealth of information. I was under the belief that a change in mufflers, especially the right muffler assisted in the over all HP increase. But from reading you guys post, i guess that's not the case.

 

True dual exhaust is a definite benefit if there is a cross-over built into the system and the pipes are not too large. For any gas driven engine under 400 HP, not more than 2.5 inch pipes. Has to do with air scavanging which pretty much syphons/sucks exhaust out of the non-firing side of the engine increasing flow capability.

A single in dual out exhaust system doesn't do any more for performance than a single pipe. All for looks.

Advantages of the single pipe, has to do with air density. The hotter the air is, the less dense it is. The objective is to be able to move the exhaust from the engine to the outside air with as little cooling as possible. As air cools (when the flow slows down in the muffler) the air gets more dense and literally starts to back up. (backpressure) That is the advantage of the single pipe for most of us is that there is much less pipe surface area to allow cooling, therefore keeping the flow constant from entrance to exit (with of course the need for a free flow muffler to really help). Also, pipes that are oversized do more harm than good because of this factor.

Personally, I can not see paying $(big bucks) for a cat back exhaust system that does no more than replacing the muffler we already have. Dodge has the perfect setup already if the stock muffler is replaced with a free-er flowing one. Stainless from tip to tail.

If you are up to it, try this if you don't want to add a tip to it.
On the tail section of the exhaust pipe, start wet sanding with 400 grit. Get it all nice and smooth and evenly sanded. You will know when. Then do it again with a series of 800 grit, then 1500 grit. Then get the Mothers aluminum polish out and you will see it shine like chrome!

 

Well fella's i picked up my FlowMaster Super 40 Muffler, and had to search for a shop to install it. I went to a total of 6 shops before, I was able to find one who would install it. Then, he couldn't install it because it was an inset as opposed to a offset muffler. So in short, he could have installed it with the muffler I had, but that means he would havehad to bend, and attach a pipe to make it fit, for a total of 2 hours labor charges, plus the cost of the additional pipes. Amazing.
Now one shop wanted to charge me $186.00 to install it, while the others wouldn't do it because i didn't purchase the muffler from them. ..So, i had to go back to PEP boys and exchange the muffler for the one which will fit, with minimal bending of pipes which will take a couple of days more...So i have to wait a couple of days more before i can have it installed.
Well Fella's that's life in the Maryland/D.C. area.

 

I will add my two bits here...

The y pipe on the hemi ex system is what kills the performance and mileage. I had a cut back ex put on my 2500 ram hemi and it helps with performance and mileage, but for the cost of the conversion it's going to take a while for the meager mpg gain.

Above 2000 Rpm my ram 2500 is a monster, but it's a 6 sp, so I really don't see the performance until I'm crusing on the high way, granted, thiers a improvement in mileage and power and I like the sound and when towing on hills, the new ex system woke up the hemi 10 fold, but if your a A to B driver who never works your truck or tows, I don't see the benifit in swapping out the stock EX.

My ex pipes run out the rear right side of the truck, the more twist's and bends to go arround your rear tire hinder flow and cost more to bend.

I don't have any regrets in swapping out the stock EX system.