sandwedge

Is this before/after assessment with or without the factory center muffler still on the car? Just asking since you also get waaayyy better sound by ditching the center muffler in favor of various versions of x-pipes.

swoardrider

First exhaust mod I did was ditch the center muffler for the Fabspeed x-pipe. That helped the sound a bit with PSE open. PSE closed, sounded about the same as having the stock center muffler. Adding the headers/cat made the car sound "tougher". with PSE closed, but muffled at 1/2 throttle and above. PSE open, "tough" sounding at idle, but "mean" sounding at 1/2 and above throttle, yet not annoying. I've been around a lot of vintage Porsche race cars, and the header/cat/x-pipe combo sounds a little like a Porsche race car, minus the ear piercing loud decibels. As the owner of Fabspeed said on another thread, "best sounding street combo for a 997 GTS is: PSE open, stock side mufflers, Fabspeed headers/cats/x-pipe". I followed his advice, and am completely happy. 😊

TheLex

Your sig states you're in the People's Republic of Kalifornia. How'd you pass smog here with headers and 200 cel cats? I thought those things won't pass?

swoardrider

Haven't crossed that bridge yet, but I'm keeping all my stock exhaust just in case I have to swap headers every 2 years to pass. It doesn't throw a cell, so If I pass visual, I'm good to go. Headers are pretty buried underneath our cars. Really depends on how well a smog station knows Porsches 😉

TheLex

Well I doubt any smog station knows the difference between a "plain" 997.2 and a 997.2 GTS. As long as you drive it a while and let the exhaust system develop some patina, I bet they can't tell the difference.
My worry was that the 200 cell cat would put out more pollutants, and the smog station would detect that.

Please keep us posted. I bet a number of rennlisters here in Kalifornia are very interested!

swoardrider

California smog stations don't use sniffers in the tailpipe anymore. They plug into your OBD 2 port and just make sure you don't have any codes stored in the computer related to emissions. So basically if your car has never had a check engine light come on due to some sort of change you made in the exhaust system or ECU you should be good to go

Chris M.

Bump for a sound clip of .2 with 200 cell cats.