exhaust redo on 91 sierra

[zombie69lol]

Hello all, as you can see i'm new to this forum thingy, so don't judge me or ridicule me too badly for any mistakes i may make. So, the story is, I bought a 91 sierra in immaculate condition, it had 220k on the body (no rust, undercoated every year, i'm up here in canada, where the beer is cold and the salt on the roads is plentiful) and 10k on the 350 crate motor. On it right now is some cruddy muffler with two 2.5 outlets and two stainless steel flowmaster pipes that come out under the rear bumper. It looks really nice, and it sounds..ok.. what i want to do is make it sound amazing. i would like to put a super 44 on it, thunderbolt 3 highflow cat and it looks like i'm going to need to replace the left manifold and y pipe. What i'd like to know is, what is a better setup for me to run off of the manifolds. id like to get the most performance out of the engine and i heard that the factory y pipe can be a hassle to that. also, i was wondering if any of you had any other recommendations for the muffler and the highflow cat. any advice is greatly appreciated, i'm very interested in working on my truck and making it the meanest sounding truck on my block, with the help of my father of course.

 

[SCOTTYINWV]

This (only because most shops charge $70 plus an hour to do collector work)
http://m.summitracing.com/parts/wlk-40295/media
With the y pipe section replaced with
http://m.summitracing.com/parts/flo-y250300
Then the thunderbolt 3 cat

And I will recommend a super 10
http://m.summitracing.com/parts/flo-8430152

Over the super 44. I have true dual super 44s and it just isn't loud enough. It has a good tone, but I can barley hear it with the windows up.

 

[sierra97]

ive got true dual super 44's and high flow cats, 2.5 inch from front to back with 3 inch tips, personally i love it, like scottyinwv stated, its not loud in the cab, but it does crackle when you lean on it, im just finishing up at ag school, everyone here has a 4x4 with some form of an exhaust system, only gasser ive heard that is louder is a brand new 5.3L thats true dual straight piped no cats, and it starts to crackle once you get above 1400 rpm, mine doesnt until 2200 rpm, to me it made more sense because i drive alot, all over the place, i like a quiet cab, i can probably get a video clip of my truck today if you'd like to hear that set up, my engine is a vortec 350 thou, not tbi