mglobe

I honestly don't know jack about exhaust design, but when I look at these pictures, it seems to me like there would be a lot of turbulence inside that can. It doesn't seem to me like that would be a good thing. Am I off base on this?

Gary R.

So two separate tube mufflers crossing behind the car (mounted up where the Flowmaster is) would give the best performance while lowering sound the most? I haven't measured but would think you could get 24"+ long tubes back there, maybe 2 6", then have the tailpipes turned down also. May be able to get the same size straight back too, have to look at it..

Bill Verburg

Yes, the longer the better, perforated core w/ wrap is better, larger diameter is better

here are some examples
Andial had these built for their cars, notice the long internal serpintine


here's a factory ST setup, large volume


a Burns setup w/ the largest cans for the available longitudinal space


stock 911, large volume, long perforated tubes


BMW, the dummu can absorbs and handles excess volume at high revs and releases it when the throttle closes, it does work and could be implemented on a 911.

ltusler

The ECU has been tuned by Protomotive and the O2's have been turned off or at lest prevented from setting a code.

Fly911

I have a 993 with the Fabspeed dual in/dual out muffler showed above, with equal length Fabspeed headers. To my taste, the Fabspeed muffler is too quiet, even if it's much louder than a standard 993 exhaust set up. I have made a "CUP" Y-pipe replacing the muffler, the sound is very GT3 cup like, and VERY loud! The end pipes are split open on the inside, so the two sides communicate like an X-pipe.

So far we haven't any noise restrictions here in Texas, and IMHO a race car should sound like a race car and not like a muffled sedan. I have attached some pictures of the Fabspeed muffler and the "CUP" Y-Pipe:

John@Fabspeed

Hey guys, lots of different muffler designs on here so since we just released our new RSR Supercup Exhaust, I thought it would be a good time to post our new Supercup design on here for you to take a look and let us know what you think. It saves some weight over our mufflers, has an X Pipe design to increase the exhaust scavenging for improved power and also has 4 resonators in it to tone it down a little and take off the edge. It is more intended for track use as it is louder but it also should make more power then the muffler setup due to the design. Let me know if you have any questions and this is available with our 993 RSR Header muffler kit package. Let me know what you think and I should be able to get some video of it once the weather breaks in the northeast. PM me if your interested or have any questions, enjoy your cars.
thanks,

Fly911

Alex, this is VERY interesting! How much? Would you take my old muffler in exchange? Or should I put two resonators on my already installed Y-Pipe, now that I already have made a hole in the bumper for the outlet (like a 997 GT3)?

John@Fabspeed

Hey Fly911, thanks for the feedback and yea I would just throw in a set of resonators to bring the sound down a little and it may also bring the low end power up a bit. Its more cost effective in your setup. If you go with this setup, the entire exhaust and headers will need to be replaced and you have system already setup for your center bumper conversion so I would stick with your setup. Let me know if you have any questions and PM me if you need a set of resonators for it.

Fly911

Alex, I sent you an email with some questions...