I am in the process of designing and building
 a 321 SS tang muffler for my P-port RX8 engine.
 I am using a $55 Mazdatrix RX8 flange.

 Does anybody else want one as I am having the
 SS water jet cut? It will look something
 like this. If I don't hear from anybody
 I am only going to make one and the price
 will go up if you want one later.

 If it turns out to be not quiet enough you should
 be able to use a second Flow Master muffler under the
 airplane to quiet it further. By that time the
 energy in the exhaust should be far enough down
 so the stock automotive muffler should live.
 The RX8 engine is easier on mufflers to begin with.

 I am not guaranteeing anything as the Wankel
 always surprises :)

 Paul Lamar


 HI PAUL WHAT KIND OF PRICE ARE YOU LOOKING FOR



 Jean Prudhomme



 I won't know exactly until I get it done but my wild ass guess
 is $400.

 Paul Lamar
 -what about 13b engine for rv7a  thanks for the motormount
 plans Keith-

That is down the road. I have an immediate need for my dyno engine so I will
do an RX8 muffler first. I will publish the plans however for the 13 B and
RX8 versions.

Each person has his own sets of skills and tools so some
may want to make their own. Speaking of that I am going
to Harbor Freight tomorrow and checking out a sheet
metal nibbler. If it looks like it can handle .065" thick
321 SS that may cut the cost for everyone as normally
321 SS must be water jet cut. Plasma cutting does a crappy
job on .065" thick SS. 2 mm or .078 seems to be the lower limit.

Paul Lamar

Maybe we can get Ed K to weld them up for us? How about a 20b version as
well as one to fit the 13brewtt engine?
Marc W.

I'll pass on Ed. 2/3rd of the time I had him do something he went off
on his own and messed it up. Anybody can weld SS including me :)

Paul Lamar

--


Before you start cutting and welding Paul, I have 2 thoughts for you.

#1 - Consider adding mounting tabs for a SS heat shield to the design.
We are welding some on to ours right now with a ~3/4" stand off.
We've scorched our fiberglass from the heat coming off the VAM - so a
heat shield is a must.  I'll send some photos of what we're trying
once we've got it in place.  It's more or less based on what I saw
Mark Steitle doing when he came by for a visit last summer.

#2 - Consider exactly how far you want the muffler to stand away from
the engine.  The distance in mine doesn't really allow for both the
2-pass rad and the stock oil cooler to be mounted beneath the engine
--  the KL wedges would 'bump into' the VAM / exhaust tube.  Adding a
bit more stand off room would make it easier to get both coolers under
there.  Also consider adding into the design something to hang the vam
from to carry the weight (besides the exhaust port tubes).

Mark Supinski

That is a good idea. Can be added to any internalk muffler.
Mark Steitle is a pretty good welder.

If I use a 5.5 inch diameter can I need to worry about getting into
the motor mount tubes which limits how far away from the engine
it can be mounted.

I am thinking of just supplying the water jet cut end caps and people
can fab the rest locally. Just about anybody can do that.

The money saved comes from making a bunch of end caps at one time.
The rest can be sheared by any sheet metal shop.


BTW you can buy heavy duty aluminum tape from McMaster Carr.
A lot of that scorching on the fiberglass comes from radiation
so shinny tape goes along way to mitigate that. I had to use
it on the motor mount tubes of my C182 as they are to close
to the exhaust..

Paul Lamar