eclou

I cut open an extra stock Bischoff muffler for a mod project. Looks like it is pretty much a straight thru design where the exhaust is ducted thru a "U" shaped pipe. There are 2 chambers, a larger main chamber and then a smaller chamber towards the front of the car. In each chamber the tubes are fenestrated to allow some gas and sound to expand out and dissipate. I'll get a picture up soon

IamSMC

Are you trying to do something similar to this?
http://p-car.com/exhaust/

eclou

Yes, but all I am doing is removing the steel wool and packing. I think Robin and others cut the "U" off as well. My welder is pretty outstanding. I have 3 years on an aluminum block in my 951 which he welded a cracked boss for a head stud, and this won't cost anywhere near $500

MarkD

eclou,
I am heading in the same direction. Trying to get some "real" exhaust note out of the TT without going to the full bypass.
Planning to modify that perforated pipe... remove stuffing... test, etc.

eclou

I want to avoid any ugly resonance. Theoretically if the chamber dividers and fenestrations are left alone, I am hoping that I will only get an increase in volume if soundwave geometries should stay in the same patterns

eclou

as you can see, it is pretty much a straight thru design. I would not think there is much power to be made here over the stock design.

ACEparts_com

My car was supposed to have Techart back boxes fitted from new. Looking at the image above makes me wonder if they were not in fact standard boxes. They actually corroded in places so any extra noise was probably due to the extra holes than anything else. My new Miltek back boxes look fantastic BTW (and cheap!)

TT Gasman

Correct me if I'm wrong, but I recall the old 993 motorsound muffler had a small internal bypass pipe between the inflow ond outflow tubes. Analagous to the first generation PSE on the 996, but internal not external. If you want more sound, it might be a good way to go.

dbf73

you have a link or more info on those?

ACEparts_com

http://www.millteksport.com/exhaust....?variantid=183

Around $1000 for the pair :O)

Kevin

To change the frequency or tone of the exhuast you need to bore a hole in the backwall..

Hwyranger

how do you like the sound of the milltek? can you describe it?

eclou

Here is a pic of a regular 993 muffler for comparison

MarkD

Seems to me that the TT muffler is pretty efficient as is. Less turbulence inside the can. Under pressure some exhaust gas will push through the perf pipe but it seems the easiest path is in and out via the u-shaped pipe.

Kevin,
Any idea what a hole in the divider will do to the exhaust note? Does it stay crisp? Get "burbly"?
TIA

LAT

I think I may pursue replacing my "Motorsound" mufflers on my 993 C4 Cab with TT mufflers. They appear much better flowing and I always need another project.

Does anyone have any idea where I can get a set of 993 TT mufflers.