Sports (rather than racing) 2-in, 2-out, no heat, exhaust?

[matteo68]

Yes I’ve had a look at their website and believe I can see that the ends of the muffler are vertical rather than rounded which is more period-correct?

Anyway I’ve sent them an email with my requirements and will see what they say.

Thanks for all comments and suggestions!

[matteo68]

I’ve seen some exhaust muffler outlets with ‘cookie cutters’ fitted on the ends. Whilst I’m not a major fan of the look of these compared to open / perforated outlet pipes, can anyone explain what they do or are they just cosmetic?

[Lightweight_911]

.
The 'cookie cutter' inserts in the end of original megaphones are intended to create a scavenging effect inside the megaphone which aids exhaust extraction.

They also have the added benefit of preventing the ends of the pipe from collapsing if you ground them.

Most 'aftermarket' megaphones do not have any spiral attached to the cookie cutters - those in the picture below were custom-made for my friend Kurt Zimmerman in an attempt to quieten down the ex-917 megaphones on his 3.5litre twin-plug slide-valve Ginther Tribute car (Sloop II):

[matteo68]

Thanks. I won’t be using megaphones (much too loud, although they do look very cool, especially long ones, and definitely race car-worthy), but at least I know now.

[911hillclimber]

For the last 28 years I've had a 2 in 3 out on the 3 engines I've had in my 73 911, a 2.2, a fab mech inj2.4 E/S and a mature 3.2.
The silencer is made by Liecstrich (spelling) and has the side opening Open all the time, but the centre pair capable.
This give very civil stock sound, next door friendly and when all 3 are open a glorious free breathing 911 rumble, that will upset all but those who love loud 911s.

I'm sure Turbo Thomas can make you one.

[Ralph]

I think if you run any sort of sports exhaust and have minimal sound deadening material it's wise to keep a packet of earplugs in the glovebox.

[911hillclimber]

Mine is far from uncomfortable with the 3 open, just a bit too much for people around me and the car.
Out of respect to them, I cap the two open pipes normally.

[BILLY BEAN]

I think if you run any sort of sports exhaust and have minimal sound deadening material it's wise to keep a packet of earplugs in the glovebox.

Totally agree with Ralph. The lack of sound deadening and Shutz under the car makes for a nice amplifier. Short journeys are fine but for longer jaunts I usually wear ear defenders. Already completely deaf in one ear. My modified 2 in 2 out standard and cheap mild steel (2 in 1) does not drone, is not excessively loud and does make a lovely sound. So the racket inside the car is down to lack of any sound deadening.