Bride of Frankenmuffler

[MT912RS]

Team project between Valvefloat ('68L) and MT912RS.
First you need a plan:
Supercup look and it sounds great!

[RickM]

Nice welding! Any detail on the components used for the muffler halves?

[MT912RS]

Kind of like this.

[RickM]

So, was the center section fabricated from scratch?

[ValveFloat]

Yes, we started with a couple sheets of 22ga steel, and a few feet of 2" exhaust tubing.

[carmaneddy]

Very nice work!

[Slant930]

Pretty cool. What CAD system did you use for that?

Timothy

[MT912RS]

Pretty cool. What CAD system did you use for that?

The top picture or the bottom?

[ValveFloat]

What CAD system did you use for that?

SolidWorks


SketchoCad

[Leland Pate]

Oh yeah.... Well... I Came Up with the name!

[Mr Beau]

But the real question. How does it sound? ;-)

[Bill Verburg]

You guys should go into business. There is a market for custom inlet and custom outlet mufflers that are reasonably quiet.

[MT912RS]

hmmmm... perhaps we will.

[Randy Webb]

How about fabbing a nice light wt. muffler out of Ti?

[911pcars]

"How about fabbing a nice light wt. muffler out of Ti?"

.... and to make it even more of a challenge (you like challenges, yes?), make it affordable too.

Sherwood

[lateapex911]

Interesting! Neat stuff.

I have always wondered about the insides of mufflers....

So, a few questions....

Performance?? Any gains?
Sound? Loud? quiet? Any air rushing or turbulence noise?
Weight?
Any packing?? If so, what?
Stainless?

Did you do any designs of one with outlets on the ends?

Thanks!

[Rob Channell]

Cool. Reminds me of a custom muffler I designed for my 911SC many years ago. I had the stock exhaust with the European pre-muffler (sits where the catalytic converter goes on American exhaust). I removed the muffler and had a machine shop bend me an exhaust pipe to come straight out the pre-muffler and curve to exit where the stock muffler exhaust pipe was. They welded a flange on it so it bolted right up to the pre-muffler. It was maybe a foot long overall and removed a fair amount of weight from the very back of the car. At low RPMs it sounded like a truck, but at high RPMs it sounded like something off the track. I called it the Wunderpipe.
I have to add that the Wunderpipe was not as well thought out or designed as the Bride of Frankenmuffler. I didn't even have SketchoCad.

Nice work. Thanks for the post. How about some sounds files???
Rob

[Early_S_Man]

That is some pretty neat work, guys!

Are those aftermarket headers that caused the long & wide separation inlet pipes? Bursch???

So, let me see if I got this straight ... you went from the basic idea. inspired by the factory banana, modified to sport muffler -- Solidworks 1, simplified actual layout to solidworks 2, right???

1st iteration:



... to final refinement/simplified for ease of assembly/fabrication:



... producing the final product:




One final questiopn ... how did you form the sheet into such a perfect circle?

[ValveFloat]

But the real question. How does it sound?

It sounds really good. Quiet inside the car, with a nice growl at full throttle. We will work on getting a sound clip.

So, a few questions....
Performance?? Any gains?
Sound? Loud? quiet? Any air rushing or turbulence noise?
Weight?
Any packing?? If so, what?
Stainless?
Did you do any designs of one with outlets on the ends?

Previously I was running a turbo muffler off of each header, which gave me a big flat spot from 4-5k rpm. With this muffler that flat spot seems to have been diminished. No dyno data yet.
It weighs less than a stocker, but we didn't weight it before it went on, we were too excited to hear it.
There is high temp fiberglass around the perforated pipes.
This proto is mild steel, but we have talked about going to stainless on future ones.

Are those aftermarket headers that caused the long & wide separation inlet pipes? Bursch???

I think the headers might be Bursch. I bought them used, they are RSR style, so they are the reason for the long inlet pipes.

So, let me see if I got this straight ... you went from the basic idea. inspired by the factory banana, modified to sport muffler -- Solidworks 1, simplified actual layout to solidworks 2, right???

The inspiration for the whole thing was the 996 Supercup muffler.

We went through a few design revisions trying to figure out an easy way to build it. The one we built was done in halfs mostly because we couldn't get material long enough locally.

One final questiopn ... how did you form the sheet into such a perfect circle?

With the top part of this thing. It rolls the sheet between three rollers to form the bend.

[ValveFloat]

Here is an autocross video clip of my L with the muffler.

CustomMufflerClip