X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from smtpauth03.mail.atl.earthlink.net ([209.86.89.63] verified) by logan.com (CommuniGate Pro SMTP 4.3.5) with ESMTP id 1022791 for flyrotary@lancaironline.net; Mon, 27 Jun 2005 01:43:34 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.86.89.63; envelope-from=conserreceipts@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=cDABR9IiDi2UjTbom97qO7btfIq8KWeH1iYi1T90+Fp8eC7JEYXNh/y/UJBcDWYL; h=Received:Mime-Version:In-Reply-To:References:Content-Type:Message-Id:From:Subject:Date:To:X-Mailer:X-ELNK-Trace:X-Originating-IP; Received: from [165.121.32.250] (helo=[165.121.32.250]) by smtpauth03.mail.atl.earthlink.net with asmtp (Exim 4.34) id 1DmmON-0005Xt-7l for flyrotary@lancaironline.net; Mon, 27 Jun 2005 01:42:48 -0400 Mime-Version: 1.0 (Apple Message framework v619.2) In-Reply-To: References: Content-Type: multipart/alternative; boundary=Apple-Mail-2--190155188 Message-Id: From: Hans Conser Subject: Re: [FlyRotary] Re: Single Rotor Research Date: Sun, 26 Jun 2005 23:42:45 -0600 To: "Rotary motors in aircraft" X-Mailer: Apple Mail (2.619.2) X-ELNK-Trace: 5ac105a4e8955dfc1c762eb5f2279a5694f5150ab1c16ac06b48d29827cfba20682e8ae7d6683b6aa2e62af564ff65de350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 165.121.32.250 --Apple-Mail-2--190155188 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=ISO-8859-1; format=flowed On Jun 26, 2005, at 5:38 PM, Lehanover@aol.com wrote: > > Everything affects everything. Unless there is a need to operate the=20= > engine well above 9,000 RPM, there is no need to modify the exhaust=20 > port to any great extent. > =A0 > Later closing the exhaust port (Port cut taller) extends the open time=20= > and increases overlap with the intake ports. This is quite helpfull at=20= > very high RPM. The same for early opening of the port. (Cuting it=20 > lower) there is little to be lost here at high RPM. The available work=20= > left in the charge has been reduced to near zero, and the late opening=20= > is to help sound by allowing more complete expansion before the charge=20= > is released. Radiusing the opening lip of the port gets flow started=20= > along a smooth curve where much of the flow stays along the bottom of=20= > the runner. There is some interest in removing the exhaust flow=20 > completely before uncovering the intakes. Adding the radius along the=20= > opening line and up the sides of the port does that. > =A0 > Other than removing tooling marks and smoothing the top of the port=20 > there is not much to do. You don't want flow from the top of the port=20= > in either direction. So leave the top as per factory.=A0I would reduce=20= > the chrome and iron=A0 around the port in all directions just s few=20 > thousandths to avoid any possibility of snagging an apex seal. Just a=20= > 16th of an inch or so is fine. Lynn, would it not be accurate to say that lowering the opening of the=20= exhaust port lowers the effective compression ratio? I have been=20 thinking that this may be desirable in a turbo engine. Hans Conser --Apple-Mail-2--190155188 Content-Transfer-Encoding: quoted-printable Content-Type: text/enriched; charset=ISO-8859-1 On Jun 26, 2005, at 5:38 PM, Lehanover@aol.com wrote: ArialEverything affects everything. Unless there is a need to operate the engine well above 9,000 RPM, there is no need to modify the exhaust port to any great extent. Arial =A0 ArialLater closing the exhaust port (Port cut taller) extends the open time and increases overlap with the intake ports. This is quite helpfull at very high RPM. The same for early opening of the port. (Cuting it lower) there is little to be lost here at high RPM. The available work left in the charge has been reduced to near zero, and the late opening is to help sound by allowing more complete expansion before the charge is released. Radiusing the opening lip of the port gets flow started along a smooth curve where much of the flow stays along the bottom of the runner. There is some interest in removing the exhaust flow completely before uncovering the intakes. Adding the radius along the opening line and up the sides of the port does that. Arial =A0 ArialOther than removing tooling marks and smoothing the top of the port there is not much to do. You don't want flow from the top of the port in either direction. So leave the top as per factory.=A0I would reduce the chrome and iron=A0 around the port in all directions just s few thousandths to avoid any possibility of snagging an apex seal. Just a 16th of an inch or so is = fine. Lynn, would it not be accurate to say that lowering the opening of the exhaust port lowers the effective compression ratio? I have been thinking that this may be desirable in a turbo engine. Hans Conser --Apple-Mail-2--190155188--