Originally Posted by cstyles

Recently acquired my 2007 GT3 RS and it was equipped with the Sharkwerks track exhaust - which is straight piped from the factory headers back, no mufflers. Lightweight, simple and way way too loud for me to enjoy street driving. I've removed it, sold it, and reinstalled the stock side mufflers + new Sharkwerks center bypass. Much less 'race car', much more 'sports car' and I am happy with the change but could use just a 'little bit more' but not willing to remove the side mufflers again.

On my Cayman R, I upgraded the stock headers to 200 cell high flow cats while retaining the factory PSE system and the upgrade in volume was perfect. I don't see any 997 GT3's with 200 cell cats, stock side mufflers and a center muffler delete like SW, RSS, etc... I am not concerned with heat soak or weight of the side mufflers, I am willing to trade those for the drone reduction they offer as it's not a track car. Looking for feedback if anyone has done just 200 cell headers + center bypass.

Originally Posted by jreifler

I did just Cargraphic headers and stock sides with SW center delete when I first had my .2. That was pretty damn good.

Originally Posted by RAudi Driver

You may be able to pull a little more sound out of your system by swapping out that Sharkwerks for an RSS. The RSS is a bit louder and doesn’t taper off in sound at the top of the rev range.

if you’re going to do 200 cell cats, may as well just pick up a set of headers with them already installed. HJS 200 cells are getting pricy.

Originally Posted by cstyles

Gert Carnewal out of Belgium offers a service of opening the stock manifolds along the factory welds, removing the stock cats & replacing with HJS HD 200 cell, and then tig welding it all back together along factory seams. Modification cannot be visually detected (if that matters for anyone's smog inspection requirements such as California) and is much less $ than buying aftermarket headers with 200 cell cats. I had Carnewal do the stock manifolds on my Cayman R and the work was perfection, at less than half the price of a set of aftermarket headers. That was 2021, I am sure the cats have increased in price but based on what I see 997 GT3 aftermarket sport headers selling for, I can't imagine the Carnewal change-out cost being anywhere close to a set of soul / fabspeed / cargraphic headers.

Thanks for the feedback, glad to hear @jreifler has done it and it's enthusiast approved.