Generation IV External Engine - No Cats vs Hi Flow Cats??

hey guys i was wondering what the difference would be on an 05-09 Corvette C6 with either the LS2 or LS3, am making a list of mods that i plan on getting once i get the car and am not dead set on getting a certain year/model yet. i actually have 2 questions:

1. which are better; American Racing, Kooks, or LG Motorsports longtubes?

2. what is the hp/tq difference when running no cats vs running hi flow cats? i want the most hp/tq i can get but am scared with no cats it will be loud and poppy sounding like glass packs. i hate that sound.

sorry if some think this is a stupid question but im new to Vettes and am just getting opinions & ideas. thanks in advance.

Ive run this test, hi flow cat vs test pipe, on an engine dyno before with a full Dynatech headers back setup and there was a 3-4hp difference on a 535hp LS1.

Run the cats, itll save you possible fines, it wont pop, and you wont feel the difference of 3-4hp, which is only 2rwhp or so.

Ive run this test, hi flow cat vs test pipe, on an engine dyno before with a full Dynatech headers back setup and there was a 3-4hp difference on a 535hp LS1.

Run the cats, itll save you possible fines, it wont pop, and you wont feel the difference of 3-4hp, which is only 2rwhp or so.

alright man thanks for the help. and do you know if it will pop without the cats?

also what headers to go with? American Racing, Kooks, or LG Motorsports?

The Dynatech setup, headers/cats/cat back, was really a nice piece. I dont have experience with the others.

The Dynatech setup, headers/cats/cat back, was really a nice piece. I dont have experience with the others.

oh okay.

hey guys i was wondering what the difference would be on an 05-09 Corvette C6 with either the LS2 or LS3, am making a list of mods that i plan on getting once i get the car and am not dead set on getting a certain year/model yet. i actually have 2 questions:

1. which are better; American Racing, Kooks, or LG Motorsports longtubes?

2. what is the hp/tq difference when running no cats vs running hi flow cats? i want the most hp/tq i can get but am scared with no cats it will be loud and poppy sounding like glass packs. i hate that sound.

sorry if some think this is a stupid question but im new to Vettes and am just getting opinions & ideas. thanks in advance.

My 427ci in my sig started out with Random Tech high-flow cats. Like a dummy I had a shop gut them. Absolutely zero performance change, but I did get a little louder and through 2nd gear a little into 3rd gear with a medium acceleration I have that choppy, poppy exhaust sound. Under hard acceleration it sounds smooth and normal through all gears. If you want it to sound smooth and definitely be a little more quiet....use the cats.

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haha alright, thanks for the advice man i appreciate it.