NO CAT VS CAT

[swathdiver]

I've seen people beat or press a piece of pipe straight through their stock cat. You keep your original cat so it looks and fits like OE, but it has a smooth path through it. I'm unfamiliar with the setup of the NBS exhausts, but this may be another option for you.

Lots of guys did this back in the day and it did not improve performance over a plain gutted cat, all that talk about disrupting flow was from the same types selling throttle body spacers and vortex generators between the air filter and throttle body. When I had my race shop, I made 90% of the cars go faster by removing all the crap they'd been sold that was utterly worthless for making horsepower.

 

[Rocket Man]

I've seen people beat or press a piece of pipe straight through their stock cat. You keep your original cat so it looks and fits like OE, but it has a smooth path through it. I'm unfamiliar with the setup of the NBS exhausts, but this may be another option for you.

I have American Racing longtubes so they're not exactly stock. The cats are their "200 cell metallic substrate" cats whatever that means. They're high flow I'm sure but I'm mainly looking to get the sound that only non-catted longtubes offer. I'm running an Aero Turbo stainless turbo muffler which sounds incredible under throttle but I still feel the sound at idle is lacking. When I get on it though it screams, the Aero muffler is actually louder than straight pipes. Perfect when a ricer is on my right and I blow his doors off.