Cupcar

I didn't think that Zeppo had such a fan base.

Here is a little blurb, note a Marman clamp held "Fat Man" the A -bomb in the Bockscar B-29 on the fateful day over Nagasaki.

http://virtualwayne.blogspot.com/201...man-clamp.html

mpotvin

Darin, Any updates on the new system?

diet97993

Marman clamps were also used on the F-4 B and J models (NAVY)in the engine bay and along the leading and trailing edge Boundry Layer Control (BLC) ducts. Just wonder if there should be a metal hard conical seal used in the joint during assembly. Just a question.

Don

CarreraX

Here is the update we have been waiting for!!
https://rennlist.com/forums/993-foru...at-videos.html

vanguard

I raised this earlier but just curious FD, how come the idea of the right header connecting to the left muffler and vice versa wasn’t used in the prototype design? Maybe it's a packaging limitation but that’s what I did on my custom 200cat setup. It looks great nonetheless but I just remember reading full 180degree bends is equivalent of adding "x" feet of tubing for the evacuating gas. I really need to get a set of Stage II exhaust. They sound great combined with the 200cell cats (saw the video).

I'll snap a picture of mine later but it looks similar in idea to this.

CarreraX

Just found out that mine have shipped and will be here Wednesday!!!
https://rennlist.com/forums/993-foru...ml#post9865524

Aircooled Dave

Exactly what I was thinking. Although the 993 exhaust routing was a huge improvement over the 964, it seems like it's not nearly as efficient as it could be given the number of bends in the system. Overall length is probably near equivalent to what you would get with a standard front engined car, which seems odd given the engines rear placement.

Not to get overly technical here, but when analyzing fluid dynamics, the Reynolds number (Re) does indicate that a 180deg bend is significantly worse when compared to lesser bends. I don't have the exact parameters of the Porsche exhaust characteristics here, but in previous work that impact can be as much as 30-40% loss in flow, whether it is laminar or turbulent in type.

The "over/under" design does seem like it could fit and in theory should be a better performer, but I have never messed with this to any degree. Even if the pipe size was physically smaller in diameter, it could in theory still be better performing than the 180deg large pipe. It would be interesting to see what comments others with more experience working on this exhaust may have.

Cheers,
Dave

bart1

My Dansk 100 cell split flow are left to right, no 180s. No pics handy.