Mat,

                  As usual I have no idea.  I made all 3 slip joints and to date no grief in that area.  I am coming around to the stock manifold in some way.  Yes it is heavy, but appears to muffle the noise as well.  Know of 2 installations that use the stock manifold with a simple muffler after and both claim "acceptable" noise. It appears that the stock manifold has a big influence on noise??  Would prefer a DB reading, but if not available it is what it is.  All is compromise, weight, cost, time, but at the end of the day it has to work. 

Still working on the turbo even though the world is on holidays.  All to save my hearing.  So far the rotary is definitely "unique" as far as a turbo is concerned.  The heat generated exceeds all else.  Two things to date -- special exhaust wheel and water cooled bearing body =, all for heat.  Have modified the stock front plate on the renesis to take an electric water pump.  That is the simple bit.

Neil.

okay I found a good company called SPD Exhaust. They have everything you need in 321ss.

With the engine being an RX8, we have three exhaust ports. Should I weld the front and back solid to the muffler, and make the middle one a slip fit for expansion? Or vice-vesa?

- Matt Boiteau

On 2019-12-28 11:03:42 AM, Finn Lassen finn.lassen@verizon.net <flyrotary@lancaironline.net> wrote:

I did something similar with my RV-3 13B decades ago. It split open at the welds around one of the pipes from the manifold into the the big outer tube. True, it did use individual manifold base plates, not the connected factory manifold and the big tube was only 0.035.

Still, I would recommend slip joints on two of the three pipes, like I added on one of the pipes (cut through and a surrounding bigger pipe -- missing in picture).



Can't remember why I went from the above to individual runners into a perforated pipe under the fuselage. Probably got lured by promise of increased power by tuned lengths and still uncomfortable by the muffler being inside the cowling.

Finn

On 12/28/2019 12:10 AM, Matt Boiteau mattboiteau@gmail.com wrote:

This is what I'm going to try in a few weeks. 

"Exhaust valve opens and a pulse of hot gas puffs out through a short pipe, then tangentially into a cylindrical canister. Being tangential, the pulse flattens out and travels helically (rather than bouncing and reverberating around) along the inside curved wall of the can, spiraling toward the exit, where it comes out more uniform in flow and so pretty quiet."

Outer pipe = 321 ss 0.050 thick. Flat plate bent to a 5" tube

Inner pipe = 321 ss 0.036 thick. 2.5" diameter

(I might use 302ss 0.065 since I already have it)

From my understanding, the area of the holes should be double the area of the inner pipe. 

- Matt Boiteau