X-Virus-Scanned: clean according to Sophos on Logan.com
Return-Path: <alventures@cox.net>
Received: from fed1rmmtao104.cox.net ([68.230.241.42] verified)
  by logan.com (CommuniGate Pro SMTP 5.2.3)
  with ESMTP id 2961428 for flyrotary@lancaironline.net; Tue, 10 Jun 2008 09:53:03 -0400
Received-SPF: none
 receiver=logan.com; client-ip=68.230.241.42; envelope-from=alventures@cox.net
Received: from fed1rmimpo03.cox.net ([70.169.32.75])
          by fed1rmmtao104.cox.net
          (InterMail vM.7.08.02.01 201-2186-121-102-20070209) with ESMTP
          id <20080610135218.GHNV2752.fed1rmmtao104.cox.net@fed1rmimpo03.cox.net>
          for <flyrotary@lancaironline.net>;
          Tue, 10 Jun 2008 09:52:18 -0400
Received: from BigAl ([72.192.137.74])
	by fed1rmimpo03.cox.net with bizsmtp
	id cDsQ1Z0031cVYgg04DsQTj; Tue, 10 Jun 2008 09:52:24 -0400
From: "Al Gietzen" <ALVentures@cox.net>
To: "'Rotary motors in aircraft'" <flyrotary@lancaironline.net>
Subject: RE: [FlyRotary] Re: Exhaust and Muffler designs.
Date: Tue, 10 Jun 2008 06:52:24 -0800
Message-ID: <000b01c8cb09$983fee90$6401a8c0@BigAl>
MIME-Version: 1.0
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
X-Priority: 3 (Normal)
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook, Build 10.0.6626
Importance: Normal
In-Reply-To: <list-2960719@logan.com>
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198

Anyway, I'd be tempted to convert your rear bracket to "soft" point, =
just by

making it a clearance fit. Or you could say "bull", and just inspect the =

weld adjacent and the attach surfaces every X hours.

Al;

If the manifold muffler were decoupled from the engine, then the rear
bracket would also need to be de-coupled.  I've chosen to have the =
entire
system rigidly mounted to the engine.  Floating the rear bracket would =
cause
something to break. =20

I don't think there is going to be any visible "sine wave" in the short
length of 2 3/4" pipe.

Al G