X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from rtp-iport-1.cisco.com ([64.102.122.148] verified) by logan.com (CommuniGate Pro SMTP 5.0) with ESMTP id 813295 for flyrotary@lancaironline.net; Thu, 03 Nov 2005 09:59:00 -0500 Received-SPF: softfail receiver=logan.com; client-ip=64.102.122.148; envelope-from=echristley@nc.rr.com Received: from rtp-core-1.cisco.com ([64.102.124.12]) by rtp-iport-1.cisco.com with ESMTP; 03 Nov 2005 06:58:11 -0800 X-BrightmailFiltered: true X-Brightmail-Tracker: AAAAAA== X-IronPort-AV: i="3.97,287,1125903600"; d="scan'208"; a="14477408:sNHT21572248" Received: from xbh-rtp-201.amer.cisco.com (xbh-rtp-201.cisco.com [64.102.31.12]) by rtp-core-1.cisco.com (8.12.10/8.12.6) with ESMTP id jA3Evvcu011193 for ; Thu, 3 Nov 2005 09:58:09 -0500 (EST) Received: from xfe-rtp-201.amer.cisco.com ([64.102.31.38]) by xbh-rtp-201.amer.cisco.com with Microsoft SMTPSVC(6.0.3790.211); Thu, 3 Nov 2005 09:58:05 -0500 Received: from [64.102.45.251] ([64.102.45.251]) by xfe-rtp-201.amer.cisco.com with Microsoft SMTPSVC(6.0.3790.211); Thu, 3 Nov 2005 09:58:04 -0500 Message-ID: <436A257C.6040403@nc.rr.com> Date: Thu, 03 Nov 2005 09:58:04 -0500 From: Ernest Christley Reply-To: echristley@nc.rr.com User-Agent: Mozilla Thunderbird 1.0.2 (X11/20050317) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Rotary motors in aircraft Subject: More on the new muffler Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 03 Nov 2005 14:58:04.0913 (UTC) FILETIME=[FE733610:01C5E086] ****Begin***** As always forget to include all the info. My engine is NA and built up by Bruce with induction porting or what ever he does. The program I used can be found under "software" at www.mh-aerotools.de/airfoils/ Its easy to use and do what ifs. Would have liked more attenuation at 500 hz but limited by volume again. I increased the diameter of the inside tube and the exhaust tube to 2.5", but kept the same length dimensions. I got back the rpm loss from back pressure. The dominate noise in cruise is still the wind and not the engine even though more horsepower is being produced. Todays results: RPM DB a DB c Idle 2K 87 102 runup 3K 90 106 climb 5.6K 100 110 cruise 6K 99 108 cruise 5.7K 99 107 cruise 5.7K 99 107.5 taxi 2K 86 100 stop 1.7K 81 99 Again did not note any major discoloration of the can or tubes. Looks like it will last for a time. May decrease the pitch on the Warp Drive prop a 1/2 degree or so. It helps to have cooler temps for performance. TNX Larry -- ,|"|"|, | ----===<{{(oQo)}}>===---- Dyke Delta | o| d |o www.ernest.isa-geek.org |