Hows it going everyone! Im looking into running dual exhaust on my 8.1. I really wanted to run duals and have the both dump right behind the rear axle but theres the shock in the way. I was also looking into having them dump right in front of the rear axle but i didnt want it to look tacky with the pipes hanging down. My last resort would be running them behind the rear tires on like a 45 and angled down a bit. Does anyone have pictures of what they have come with?:help:

Need more info on your specific truck.

From what I understand, dual exhaust is somewhat difficult if you have AutoRide as there are fitment issues.

Its a ext. cab long bed. I dont have air ride. the left rear shock is what i saw maybe getting in the way.

Run 3 inch to 2 1/2 inch then you bend the pipe however you want plus itll be louder that way

Id really like to have big piping like a diesel but i know im not going to have enough back pressure.

How big of pipe you lookin at?

i got 3" all the way with no problems

i got 3" all the way with no problems

do you have any pictures of how its run?

look up "SW LT Headers and Magnaflow" on here. i have pics in there, but dont remember how many

How does going from 3 to 2.5 make it louder? Does it make it really kacklly? I have 3 inch all the way bck 45 behind the rear wheels with 40 series flows behind a vortec 454.

Flowmaster is horrible shit id chop that exhaust and put somethin else on it

i had dual 40 series on my 5.7 and loved them. i want something smooth and loud! im not a big fan of how poppy these trucks get when you put exhaust on them. Im thinking magnaflow is going to be the way to go.

Im thinking magnaflow is going to be the way to go.

i thought the same thing til today. i didnt run duals but i replaced the stock muffler with a magnaflow #12599 3''dual inlet/3'' dual outlet, drove about 50 miles and 3 hours later i was back at the muffler shop putting the stock muffler back on. the resonance in the cab was unbearable. the truck definately ran stronger but i couldnt tell how it sounded outside because it was too loud inside. this was on a 06' 2500hd w/6.0L. talking to the muffler shop, they seem to think any configuration of magnaflows would have the same result unless a resonator was added. anybody have any other muffler suggestions, besides flowmaster? flo-pro maybe?http://www.flopro.com/FP2500oval.htm

i thought the same thing til today. i didnt run duals but i replaced the stock muffler with a magnaflow #12599 3''dual inlet/3'' dual outlet, drove about 50 miles and 3 hours later i was back at the muffler shop putting the stock muffler back on. the resonance in the cab was unbearable. the truck definately ran stronger but i couldnt tell how it sounded outside because it was too loud inside. this was on a 06' 2500hd w/6.0L. talking to the muffler shop, they seem to think any configuration of magnaflows would have the same result unless a resonator was added. anybody have any other muffler suggestions, besides flowmaster? flo-pro maybe?http://www.flopro.com/FP2500oval.htm

I have dyna mat everywhere in my truck, so outside noise isnt really in the question for me, my buddy put a "corsa" i think the brand was on his 6.0 and it sounded pretty nice. it wasnt the tone im looking for i want a nice deep roar with the lease krackle and pop possible.

i thought the same thing til today. i didnt run duals but i replaced the stock muffler with a magnaflow #12599 3''dual inlet/3'' dual outlet, drove about 50 miles and 3 hours later i was back at the muffler shop putting the stock muffler back on. the resonance in the cab was unbearable. the truck definately ran stronger but i couldnt tell how it sounded outside because it was too loud inside. this was on a 06' 2500hd w/6.0L. talking to the muffler shop, they seem to think any configuration of magnaflows would have the same result unless a resonator was added. anybody have any other muffler suggestions, besides flowmaster? flo-pro maybe?http://www.flopro.com/FP2500oval.htm
X2 on the magnaflow

i think thats the magnaflow muffler i have. 3" dual in/out with the built in x-pipe. i dont think the resonance in my cab is that bad.

Are you guys dumping your exhaust out the muffler? I did that on a 00 6.0 and noise in the cab was bad so on my 99 454 i ran it out behind the tires and its a lot better. A muffler shop said any type of pipe off the muffler will help.

Are you guys dumping your exhaust out the muffler? I did that on a 00 6.0 and noise in the cab was bad so on my 99 454 i ran it out behind the tires and its a lot better. A muffler shop said any type of pipe off the muffler will help.

mine has the stock exhaust all the way out the back, i only replaced the muffler.

mines ran all the way out the back.

These 8.1 are the easiest to put duals on of any truck I have done. They are dual 3 inch to the muffler, so all I did was to cut the muffler and tail pipe off and weld two Dynomax Super turbos and 2.5 inch tailpipes angled out the back. I put an H pipe in before the mufflers and I ran the passenger bank of cylinders out the drivers side rear and vice versa to balance the length of pipe in the entire system. I have very little to no drone in the cab, and a nice deep tone. On these trucks, the drivers side bank of cylinders has go across the truck to the passenger side and then down to the rear axle and then back across if you have tailpipes after the axle. By criss crossing the tailpipes, you get a more balanced system and it flows much better. I posted some pictures of my exhaust some years ago, not sure if I still have the pics.

I kept the tailpipes at 2.5 inch for 2 reasons. One the muffler shop couldn't bend 3 inch pipe, and two I wanted to create some scavenging effect in the exhaust system by keeping the velocity of the exhaust faster to create draw out of the cylinders.
To large of pipe, slows down the speed of the exhaust and makes the engine have to push it out. However, a tuned system, actually will help pull it out. This creates more power down lower in the rpm range where these trucks run most of the time. It is not as good at WOT, but how often do you run your truck at WOT?

Flowmaster is horrible shit id chop that exhaust and put somethin else on it
I know its a completely different motor and is old school technology, but i have true duals, headers back into 2 flowmaster 44s on my 79 chevy with a mild 454, and i absolutly love the sound, and think it is by far the best sounding truck around where i live.. that being said, i have a 84 chevy with a stock 350, and when i got it the muffler was rotted out right under the cab, so i just took a piece of 2 1/4 old used pipe and strait piped it for the time bein and thought it sounded like crap..so its not just cause its mine that i love it..they are around 60 deg bend out the sides with 5inch tips and its has alot of tone just cruisin and isn't horribly loud, but make it hit passing gear and its loud as hell...i wont owne a set of 40s, i just don't like the way they sound. best best is just to get on youtube and try to find 8.1s with duals..but theirs alot more 6.0s than them. thats what made me choose the 44s......and a friend of mine has some kinda magnaflow on his 07 5.3 dual exhaust, and it sounds damn good going down the road, it just isn't very loud. it does cakle and pop alot which is not a good sound to me.

Hey apayne86,

Thanks for the great words on Flowmaster (http://www.flowmastermufflers.com/) mufflers. Big Block’s and 44’s (http://www.flowmastermufflers.com/shop/index.php?main_page=product_info&cPath=0&products_id=4232&ab=842446&recordID=&vehicle=&orig=842446) go great together.
Don’t forget to look at Hushpower (http://www.hushpower.com/) mufflers. The Hushpower (http://www.hushpower.com/) has a distinct throaty sound.

Here’s a link to a video of testing Hushpower (http://www.hushpower.com/) mufflers on a Chevy 406: Hushpower Muffler Sound Testing

Check out videos on the Hushpower website (http://www.hushpower.com/): CLICK FOR VIDEOS (http://www.hushpower.com/categories/204/%3Cfont+color%3D%22%23FFFFFF%22%3EVideos%2FSounds% 3C%2Ffont%3E.html)

Here’s a chart to help you choose a muffler by interior and exterior sound levels:
http://i997.photobucket.com/albums/af92/kahnmedia1/FamilyofMufflersFinal2-med.jpg

The Flowmaster (http://www.flowmastermufflers.com/) and Hushpower (http://www.hushpower.com/) mufflers are available in Aluminized Steel and 409Stainless Steel.

Have a Great New Year!