lol just kidding.. BUT

i have an 05 LS with dual (y-piped) flowmaster 40 series muffler with centerline 2.5" dual outlet tips

now nothing else is done but the y-pip, mufflers, and tips but im wanting a louder tone to it

so what else can i do? i dont wanna take out the cat and i dont want an aftermarket one, so is there ANYTHING i can do? i wanna take out the resonator, will that help?

let me know!

 

Resonator will help.

Why wouldn't you want an aftermarket cat? A high-flow cat will benefit you greatly!

The only other thing you could do it drop a 3800 in there :P

Or even do a CAI.

 

Bingo. that resonator is a big restriction on the sounds your car will make. try removing that first. You could replace it with a glass pack or something, but that CAN make the car sound kinda crappy. I know you dont want an aftermarket cat, but I do also agree with chibiblacksheep... if the resonator doesnt give you the tone you want, the cat would be what your looking to swap out next.