Hello,
RO-Jett 76 rear exhaust for stunt may be equipped with Light Header Muffler shown on http://www.jettengineering.com.
This header muffler comes with the "Muffling Part".

I wonder if anybody tried to remove the "Muffling Part" and do this what I am going to do.

Please see the attachment.

Your comments are appreciated.

Thank you,
Matt

Steve,
Let me explain what I am trying to do:
I will compare 76 with Lite Header Muffler to 76 with Lite Header ONLY connected to the pipe.
Light Header Muffler I am getting from Dub Jett, will have the "Muffling Part" not attached and I will play with it myself.
Specifically, I will install the "Muffling Part" in such a way that it will be removable and properly sealed while in place.

Lite Header has OD=7/8" and the coupler I have will allow me to connect it to the Windy's pipe.
There will be a minute mismatch of diameters ( Windy's pipe inlet OD is greater than 3/4 but smaller than 7/8 ) though.

Will this affect anything? I do not know therefore I will check it.

Windy's pipe I have is primarily a muffler ( cylindrical aft part ) and I may benefit from simply not having it in my next, large model.

Instead, I may use 76 with Lite Header AND the Muffling Part installed.

Weight savings will be around three oz. and everything will be simpler. When the prop is selected, all I will have to do is to get 4 cycling on the launch and fly.

Regards,
Matt
 

Will this affect anything?

According to your diagram you will have a step in the gas flow at the start of the custom made adapter or where the ID narrows down.

Will this act as the first baffle or reflective wall? I kinda doubt it since it is tapered and should be no more disruptive than the normal flange to pipe weld (both rear and side exhaust) further up stream.
Or will the added volume of the header pipe interfere with the state of tune? No idea.