X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [65.54.250.77] (HELO hotmail.com) by logan.com (CommuniGate Pro SMTP 5.0.8) with ESMTP id 970278 for flyrotary@lancaironline.net; Sat, 04 Feb 2006 18:04:41 -0500 Received-SPF: pass receiver=logan.com; client-ip=65.54.250.77; envelope-from=lors01@msn.com Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sat, 4 Feb 2006 15:03:57 -0800 Message-ID: Received: from 4.171.129.64 by BAY115-DAV5.phx.gbl with DAV; Sat, 04 Feb 2006 23:03:57 +0000 X-Originating-IP: [4.171.129.64] X-Originating-Email: [lors01@msn.com] X-Sender: lors01@msn.com From: "Tracy Crook" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Mazda mufflers Date: Sat, 4 Feb 2006 18:03:53 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00C7_01C629B5.5BB07C30" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: MSN 9 X-MimeOLE: Produced By MSN MimeOLE V9.10.0011.1703 Seal-Send-Time: Sat, 4 Feb 2006 18:03:53 -0500 X-OriginalArrivalTime: 04 Feb 2006 23:03:57.0231 (UTC) FILETIME=[4700ABF0:01C629DF] This is a multi-part message in MIME format. ------=_NextPart_000_00C7_01C629B5.5BB07C30 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I thought the most significant result of the muffler experiments at the = rotary roundup was the small diameter tail pipe we tried. Don't know if anyone got sound meter readings but the muffler was = significantly quieter with the small tail pipe installed (about 1" in = diameter!) Obviously more restrictive but what amazed me was that the = WOT rpm of the engine was only 100 - 200 RPM less than with the straight = thru experimental muffler. I'm starting to think in terms of an easily = removable necked down tail pipe extension for times when I'm more = concerned with quiet flight than max performance. =20 Tracy (never going to build another home-made muffler / satisfied with = the Flowmaster Hushpower II) Thank you very much for your muffler report David! I did have a tangental muffler on my bird for five years, and it was = nice and quiet. But it was welded by a welding shop, and the welds were = cracking, so I went to straight pipes. I like the lower cowl temps, but it = really is too loud. Now, we must wear headsets. I have a "Welders Blanket" cloth which is supposed to handle over 2300 = degF. I am hoping that I could use that for "glass packing". The "almost empty can" demonstrated at Tracy Crooks Rotary Roundup = sounded good enough for my needs. George Graham Mazda Rx7ez N4449E Sarasota Florida -SRQ=20 -------------------------------------------------------------------------= ----- Yahoo! = Messenger- Start an email = from Y! Messenger, plus be alerted when new emails arrive. ------=_NextPart_000_00C7_01C629B5.5BB07C30 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

I thought the most significant result of the muffler = experiments at=20 the rotary roundup was the small diameter tail pipe we tried.

Don't know if anyone got sound meter readings but the = muffler was=20 significantly quieter with the small tail pipe installed = (about=20 1" in diameter!) Obviously more restrictive but what amazed me was = that=20 the WOT rpm of the engine was only 100 - 200 RPM less than with the = straight thru experimental muffler. I'm starting to think in = terms=20 of an easily removable necked down tail pipe extension for times = when I'm=20 more concerned with quiet flight than max performance.

Tracy (never going to build another home-made muffler = / satisfied with=20 the Flowmaster Hushpower II)

Thank=20 you very much for your muffler report David!

I did have a = tangental=20 muffler on my bird for five years, and it was nice and
quiet. = But it=20 was welded by a welding shop, and the welds were cracking,
so I = went to=20 straight pipes. I like the lower cowl temps, but it really is=20 too
loud. Now, we must wear headsets.

I have a = "Welders=20 Blanket" cloth which is supposed to handle over 2300 degF.
I am = hoping that=20 I could use that for "glass packing".

The "almost empty can"=20 demonstrated at Tracy Crooks Rotary Roundup sounded
good enough for = my=20 needs.

George Graham
Mazda Rx7ez = N4449E
Sarasota=20 Florida -SRQ=20

Yahoo!=20 Messenger- Start an email from Y! Messenger,
plus be alerted = when new=20 emails arrive.

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