I have a 97 GMC Sierra K1500 with a 5.7 Litre.
I just bought a dual cat-back kit from Flowmaster (#17187) and am just about to install it. I am concerned because it comes with a 70 series Big Block 2 muffler, which is Flowmaster's quietest muffler!
I want to hear my new exhaust!... Will I be satisfied with this kit?
Any opionions are greatly appreciated.

 

nope its gonna be close to stock

 

I agree! You're not going to be satisified, I promise you. If you want some loud agression, you need to go with an original 40 series, single in dual outlet since you are going cat-back.

 

Thanks guys.
I ended up installing it anyways, and I am happy with it.
It is surprisingly loud when I want it to be, and quiets right down when I don't. It sounds great, and WAY louder than stock.

I agree that the 40 series would be very aggressive, cause this kit sounds sweet too!

 

I'm glad it worked out for ya bro! It's always good to hear a success story!