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Custom exhaust question for 996 C4S

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YOUR RESEARCHCustom exhaust question for 996 C4S

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POST 1 / ORIGINAL POSTEROriginal post

I am thinking at a slip on muffler setup that is for a newer 911 that I would like to retrofit to my C4S. As I understand it now, the mufflers are in the cheeks (as I call it) and the cats are in the cross section correct? Since the muffler I am purchasing is designed to be in the center, can I / or has anyone here mounted the cats in the cheeks and had them pass through a center muffler(s) out to the tips? - I hope I'm making sense?

POST 2 / ORIGINAL POSTEROriginal post

Going to this...without the turbos

POST 3Original post

I looked into doing this myself when I first got my C4S. The dimensions of the center piece where the current y-pipes cross looked to be the most difficult part. Then came mounting as there isn't much there to provide support. Ultimately went with known products. If you're able to figure it out let us know! Would be awesome to see

POST 4Original post

I mean, yes I believe it is possible. You will have to fabricate some new mounting locations though.

POST 5 / ORIGINAL POSTEROriginal post

Thank you guys. I will pursue this because YOLO I believe it will be an efficient setup since that is what Porsche eventually went to through their development. I will post pics and details once we start. There are two options that I'm thinking about : 1. Muffler / Cat by pass in the cross section, then clear the codes 2. Something like this...See picture (991 C2)

POST 6Original post

any updates on the custom exhaust?? im thinking of doing something similar to my C4S

POST 8Original post

that's clean!!! any sound clips or info on the exhaust setup??

POST 9Original post

Looks great. What is the purpose of the dead end 4th pipe on each side? Were there only 4 pipe merge collectors available and the best way to cap it off was to have a longer tube for resonance reasons?

POST 10Original post

Not sure I follow, but if you�re ultimately after a center exit exhaust, it has been done by a few rennlisters, here�s one I recall: https://rennlist.com/forums/996-foru...996-c2-c4.html

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