Hey guys I know there are tons of threads on exhaust systems setups. I have a 2004 Silverado ext cab 5.3 with longtubes, air intake, custom tune, and cam XR269HR-14 216/220-.525/.532 with LS6 yellow springs. Right now I have 2.25 y-pipe with high flow cats and single 3’’ in and dual 2.5 out muffler.
I hope I can describe it to yall in words.
Driver side, starts with a longtube with then 2.5 pipe and makes the y and then the passenger side, starts with a longtube, then hi-flow cat and connects to the pipe from the drivers side. And 5 inch down the second hi flow cat, then some more 2.5 pipe straight connects to the muffler and then dump before the axles. I know my exhaust system is done all wrong. I want to redo my exhaust system. I want to make it flow better and maybe sound a little less on the highway.


The muffler shop told me he can do me a new exhaust system. Two options.
A. Hi-flow right after the longtubes and then 3’’ y-pipe and use my old muffler and have it dumped over the axles.
b. 2.5 true dual with two magnaflow mufflers. And dumped over the axles

what do yall guys think? Or do you have any other ideas?

Thanks guys.

 

set it up with no cats ! . . .


y-pipe off the headers, single 3" . . . exited right before the rear of the tire !

 

a single 3" y pipe would suite you just fine, and be easier on the wallet. anything dumped under the truck is gonna drone more. as said above, before the rear tire out the side, or dumped over the axle somewhere is gonna eliminate the most highway noise

 

Dual 2.5 would be overkill for your setup, I'd do 2.5" off the headers (cats or no cats) merging into 3" at the Y, single 3" on back, dumped as you desire. As mentioned it will be louder and drone more dumped before the axle than if you ran it over. This is pretty much my current setup (big Gibson muffler dumped before axle), which will be getting changed to an 18" 5x8 oval Magnaflow muffler with a DMH electric cutout before the muffler, and I will be gutting the high flow cats that are in my StainlessWorks y-pipe.

 

thanks guys.. Im gonna do the 3'' y-pipe. Now i just need to figure out cats or no cats.

 

i disagree with the dump before axle=drone.... i had 3" piping off of my long tubes to a single 3'' and a 20-22" dynomax dumped before the axle.... later i added a tail pipe bc my cab would stink like non catted exhaust in seconds when the truck wasnt moving.... it was basically silent at all rpms under 3k but now with the tail pipe it sounds like a fuggin flowmaster and DRONES LIKE HELL any where from 1500 to 2200 rpm........ i would go 2.5 off the headers to a single 3 inch... maby 3.5 if ur thinking of stepping up the cam later... i would also do the dump first... bc if its what you like then you saved some $$$ from the tail pipe... if not then add the tail pipe later

 

Hmmm, interesting...guess it's different for every system...