Hey Guys, new guy here with a 09 Sedan. I come from the SRT-4 and Fiat Abarth Scene.
I have searched but haven't found too much.

Cat is a daily commuter and looking to bring to car a notch above GMS1.

How restrictive is the stock DP?

I'm looking at going with a ZZP canned tune to start along with a catted dp, and then later on add some more supporting mods such as IC. I would like to keep the cat very stockish.

Catted DP worth it or just keep it stock?

Thanks!

 

IIRC all good aftermarket pipes don't have compression bends, and have a better flowing cat's.

Yes, it's worth it.

 

Swap it out. Aftermarket downpipes usually use higher flowing cats. And skip the canned tune. You're better off with a real tune.

 

Stock downpipe isn't that restrictive on a HPtuned car but you do gain alot of top end and around 10 hp from throwing one in while tuned.