I been research for best exhaust. Like loud. Which do you think I should get it? For my 2003 GMC Sierra slt ext cab auto 5.3 4x4 many thanks.

 

Round, short, borla xr1

 

the loudest option would be longtubes with around 18" of exhaust pipe off the collector dumped. it will get old fast lol

 

https://www.performancetrucks.net/fo...bullet-527356/

 

I plan leave alone with stock header and cat. Just muffler system since I bought another truck for daily drive. I already have xr1 borla on my 06 Silverado with turbo.

 

 

with stock manifolds and converters, a muffler delete doesnt sound horrible, and is about as loud as you can get before longtubes or ORY

 

Don't u think flow master worth? Or dyno max.

 

What about glass pack so can keep back pressure ok

 

You think a glasslack adds backpressure? Your stock manifolds, converters with full pipe out the back is enough of a restriction. You said loud. Im giving the loudest options. Even a bullet behind stock converters and manifolds knocks out a lot of sound.