Return-Path: Received: from smtpauth09.mail.atl.earthlink.net ([209.86.89.69] verified) by logan.com (CommuniGate Pro SMTP 4.3c1) with ESMTP id 740164 for flyrotary@lancaironline.net; Tue, 15 Feb 2005 13:04:31 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.86.89.69; envelope-from=jerryhey@earthlink.net Received: from [65.176.176.253] (helo=earthlink.net) by smtpauth09.mail.atl.earthlink.net with asmtp (Exim 4.34) id 1D1730-0005Zn-8a for flyrotary@lancaironline.net; Tue, 15 Feb 2005 13:03:42 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=simple; s=test1; d=earthlink.net; h=Date:Subject:Content-Type:Mime-Version:From:To:Content-Transfer-Encoding:In-Reply-To:Message-Id:X-Mailer; b=WY4Jk3g0rMy5NtS5QISW6Pu/pFPFOku7NIm4v/8oAKlA5W3jfnqL/q2YtJbsZNpz; Date: Tue, 15 Feb 2005 13:04:43 -0500 Subject: Re: [FlyRotary] Re: Big Butterflies, was: Bruce Turrentine Intake Content-Type: text/plain; charset=US-ASCII; format=flowed Mime-Version: 1.0 (Apple Message framework v552) From: Jerry Hey To: "Rotary motors in aircraft" Content-Transfer-Encoding: 7bit In-Reply-To: Message-Id: <11A7BE71-7F7C-11D9-8287-0003931B0C7A@earthlink.net> X-Mailer: Apple Mail (2.552) X-ELNK-Trace: 8104856d7830ec6b1aa676d7e74259b7b3291a7d08dfec7973f353ca665ac09d16f79da8464bae84350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 65.176.176.253 Bob, that does seem large. For reference, the p port has two butterflies for a TOTAL of 4.1 sq in. This was based on calculations done by Rolf and should be good up to 8000 rpm. The size is similar to what Power Sport is using and what Paul Yaw has recommended. Jerry > > Hi Tom, > > I think there is a small error in your area calc. A = pi* r^2, so > A = 3.14*(2.5625/2)^2 =~ 3.14*1.28*1.28 = 5.15 sq. in. > > I'm hoping to get the engine running pretty soon to get some idea of > how > well it is going to work. > > Bob White > > On Tue, 15 Feb 2005 08:54:12 -0800 (PST) > Tom wrote: > > >> >> So lets take your butterfly size of 2 9/16 inches. >> Bobs butterfly area = (2 9/16 / 2) x 3.14 = 4.02 square inches >> Max supported airflow based on their rule-of-thumb = 4.02 x 140CFM = >> 562CFM Max HP based on these (100HP per each 140CFM) = 402HP >> The difference between the actual HP your motor will make and 402HP is >> throttle-movement that would do nothing for you. >> >> Here's the website: >> http://www.dune-buggy.com/turbo/intake.htm >> >> Still learning stuff, >> Tom >> >> >> >> > > > http://www.bob-white.com > N93BD - Rotary Powered BD-4 (soon) > >>> Homepage: http://www.flyrotary.com/ >>> Archive: http://lancaironline.net/lists/flyrotary/List.html >