Arcese993

Ready to purchase exhaust for my C4S, I need help on what to buy, what system will give good power (that will not be too loud)

CarmG993

Nothing will give you any real power gains.
Take a look at FD Motorsports. I have the Stage II's.
http://www.fdmotorsports.net/index_files/Page1456.htm

goofballdeluxe

I, too, have a 1996 C4S. Forget out power; you won't get enough to count through an exhaust. Focus more on a great sound. I have Fister Stage IIs on my car, and they're terrific.

Canyon56

Fister Stage II for me, too....

Full Boost

Fister - the ONLY way to fly....

Arcese993

will it be too loud if I add Dach x with cad's, to the fister's?

bart1

I went a different route than everybody else. I started out by replacing the ats with Dansk split flow 100 cell sports cats. Cats are really the only thing that let you gain a fuzz of power and they also improve sound. Also, the weight is located further back on the car and, thus, better to reduce.

I do plan to add some mufflers at some point as well. Do search for the popular options here: FDMotorsports, DACH, RSRs, etc. Plenty of reading and opinions.

simpsoap

I've got Stage III's and they sound great!

Andy

Smoke

Thanks to the PO, its GHLs with LPMM “tweaking” for a better sound even sound BETTER!

Maybe RJT will post a clip.
________________________________
1996 SY C4S the best of breed

Evan Fullerton

I have Porsche Motorsports RSR headers (ok they aren't real ones but they are hand make exact replicas) directly into the stock side cans (no cat or crossover) and am quite surprised how quiet it is. It isn't street car quiet but it isn't very loud and doesn't sound like a motor boat like cars with stock cats. If you are interested in getting rid of the motor boat sound I would recommend something that removes or replaces the stock cat.

Matt Lane

Some like Fabspeed Supercups. You could ask them, if they can hear you over the racket.

I like racket.

993inNC

Our point of critical mass has since passed
so I'll answer from a pure informative standpoint (no more shameless plugs.....)

Nothing you do cheaply will make any huge difference in power. What you'll need to do is concentrate on harnessing and best utilizing what power you have. And you do that via weight reduction. Exhaust will squeak you between 10-20 hp at best no matter what you do, but you can shed weight. Your biggest bang for the buck (depending on who does the labor) is going to a lightweight clutch and flywheel. Getting all that extra dual mass clutch weight off the rotating mass makes a huge difference. Seats are another weight pig that is a great place to shed.
Getting back to exhaust, muffs do nothing for power, pipes (mine or others) should reduce weight and add power (although I've heard the contrary and will let others chime in on that). And cat pipes will allow for power increases while staying emissions legal.

enjoy your reading.....you have a lot to filter through

Fly911

Get a set of X-pipes, with our without cats. Fabspeed, Dach, Stebro, Cargraphic and Schnell all make good X-pipes. The thing with the X-pipe is that it combines the exhaust from the two cylinder banks, so the engine exhaust sound like one six sylider rather than two three cyliders engines (not really, but sort of...). The standard 96 1/2 to 98 Gillett exhaust has one separate path for each cylinder bank (as opposed to the 94-95 and early 96 Bishoff system, where the two banks are comingled in the cat pipe). The standard Gillett split path exhaust will give fundamental and second harmonic frequency sound, but the X-pipe will also give you a fourth harmonic frequency sound, more like a high pitch GT3 like whine on high rpm. Combine the X-pipe with a set of low restriction mufflers, and you will have a good set up.

As for power, the gains are marginal from the OEM system, and power differences between the different makes are maybe even more marginal. Also, a low restriction cone air filter aslo changes the exhaust sound (it sounds strange, but it actually does), and on WOT it makes a beautiful concert for six cylinders (forget about the stereo...). With a reflash of the Motronic ECU, air intake and a good exhaust system, you should expect a healthy 300HP on your C4S. Good luck!!!

Stealth 993

This is what I have on my C4S, it's a little quiet. But has great idle sound, & really comes alive under WOT. Fit is PERFECT on both the X (with cat) pipes & mufflers. The build quality is unmatched.

I have not done another Dyno with the pipes & mufflers, but there is some top end power gain, some low end loss. But the engine feels much more eager, with better throttle response, & the engine seams more willing to rev. Of course the rear end lost a few pounds.

When things settle down, I'm thinking of going STG III's.

Here is a little sound clip.....

bart1

Part of (pretty much all of) my reason for choosing split flow cats over x-pipes. This guy is in the top 0.001% of 3.6 engine tuners, methinks, and he uses split flows. This is just one of the posts he made on the matter:


https://rennlist.com/forums/3361018-post65.html