im going to cut out both of my cats, does anyone know what size pipes i need to replace the cats? are they 2.5" i have a 97 SS, it came with the exhaust option but that after the cats. one of my cats is like a coffee can on the drivers side, the other is down the passanger side. will it make my car a lot louder? i have 3" pipes w/flowmaster

 

I don't know what size for a 97, either 2.5 or 2.75.

Do you have 02 simms to go in, otherwise your 3rd 02 sensor will throw a code at you.

Yes, it will make your car louder.

 

my SES light is already on, i have a bad secondary air pump or something like that. nope i dont have sims. will sound be differand if i run pipes insted of hollow cats? i cant get to the cat on the passanger side. i dont know how i would gut it. i would need to cut them off to gut them. might as well put pipes inplace of them