X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: <wdleonard@gmail.com> Received: from zproxy.gmail.com ([64.233.162.195] verified) by logan.com (CommuniGate Pro SMTP 5.0c2) with ESMTP id 711871 for flyrotary@lancaironline.net; Mon, 05 Sep 2005 14:40:26 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.233.162.195; envelope-from=wdleonard@gmail.com Received: by zproxy.gmail.com with SMTP id z3so946089nzf for <flyrotary@lancaironline.net>; Mon, 05 Sep 2005 11:39:41 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:references; b=nrEbUbT91J1GNmFDvfaZJ6MVG/X+rx9wNkJnYG7MJXVBC1LeBtL6B1G3Hj7J94yFoAbLWvGBdfzVjkpwDggj84mjEs4TWJFnjeOXDEqOqDbIY1SWOIZdJLy+Nay4Pqs0CaQX5kl7+nvfu5ZvQR2SgUFNQCmwsl0MzCBUUvQRENI= Received: by 10.36.79.10 with SMTP id c10mr2496428nzb; Mon, 05 Sep 2005 11:39:41 -0700 (PDT) Received: by 10.36.8.13 with HTTP; Mon, 5 Sep 2005 11:39:41 -0700 (PDT) Message-ID: <1c23473f050905113930ab8f19@mail.gmail.com> Date: Mon, 5 Sep 2005 11:39:41 -0700 From: David Leonard <wdleonard@gmail.com> To: Rotary motors in aircraft <flyrotary@lancaironline.net> Subject: Re: [FlyRotary] Re: Another great flying day = another day of troubleshooting In-Reply-To: <list-711824@logan.com> Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_23592_14011051.1125945581366" References: <list-711824@logan.com> ------=_Part_23592_14011051.1125945581366 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Ed I am talking MAP in both cases. I don't see how 26" MAP is higher than= =20 36"MAP. But I learned the old math :-) Dave On 9/5/05, Ed Anderson <eanderson@carolina.rr.com> wrote:=20 >=20 > Well, actually it is absolute pressure that the spark plug is reacting to= .=20 > In this example, the absolute pressure in the intake is 1.234" HG higher= =20 > at 10,000 with your 26 " boost than at sea level with your 36" of boost..= =20 > This would contribute to an increased pressure in the combustion chamber= =20 > when it is compressed over the sea level compression pressure. Therefore,= =20 > the spark plug is facing a tougher task at 10,000 than at Sea level (in t= his=20 > example). > Ed >=20 > ----- Original Message -----=20 > *From:* David Leonard <wdleonard@gmail.com>=20 > *To:* Rotary motors in aircraft <flyrotary@lancaironline.net>=20 > *Sent:* Monday, September 05, 2005 12:57 PM > *Subject:* [FlyRotary] Re: Another great flying day =3D another day of=20 > troubleshooting >=20 > Actually, Dave you had a higher pressure ratio (manifold to ambient) a= t=20 > > 10,000 feet with 26" boost than at sea level with 36". At sea level the= =20 > > pressure ratio would be 36/29.92 =3D 1.20. At 10,000 ft ambient pressur= e =3D=20 > > 20.57 " hg , so the pressure ratio would be 26/20.57 =3D 1.26. Not much= =20 > > greater, but it was higher by approx.1.23" Hg. (1.20 -1.26 =3D .06 *20.= 57=3D=20 > > 1.234" Hg).=20 > >=20 > > Ed A > >=20 > > Right. But what does the plug know about the ambient pressure? I though= t=20 > that it was just the absolute density of the charge that was contributing= to=20 > SAG.=20 >=20 > --=20 > Dave Leonard > Turbo Rotary RV-6 N4VY > http://members.aol.com/_ht_a/rotaryroster/index.html > http://members.aol.com/_ht_a/vp4skydoc/index.html=20 >=20 >=20 --=20 Dave Leonard Turbo Rotary RV-6 N4VY http://members.aol.com/_ht_a/rotaryroster/index.html http://members.aol.com/_ht_a/vp4skydoc/index.html ------=_Part_23592_14011051.1125945581366 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline <div>Ed I am talking MAP in both cases. I don't see how 26" MAP = is higher than 36"MAP. But I learned the old math :-)</div= > <div> </div> <div>Dave<br><br> </div> <div><span class=3D"gmail_quote">On 9/5/05, <b class=3D"gmail_sendername">E= d Anderson</b> <<a href=3D"mailto:eanderson@carolina.rr.com">eanderson@c= arolina.rr.com</a>> wrote:</span> <blockquote class=3D"gmail_quote" style=3D"PADDING-LEFT: 1ex; MARGIN: 0px 0= px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid"> <div><font face=3D"Arial">Well, actually it is absolute pressure that the s= park plug is reacting to. In this example, the absolute pressure in t= he intake is 1.234" HG higher at 10,000 with your 26 " boost than= at sea level with your 36" of boost.. This would contribute to = an increased pressure in the combustion chamber when it is compressed over = the sea level compression pressure. Therefore, the spark plug is faci= ng a tougher task at 10,000 than at Sea level (in this example). </font></div><span class=3D"sg"> <div><font face=3D"Arial"></font> </div> <div><font face=3D"Arial">Ed</font></div></span> <blockquote style=3D"PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5p= x; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"><span class=3D"q"> <div style=3D"FONT: 10pt arial">----- Original Message ----- </div> <div style=3D"BACKGROUND: #e4e4e4; FONT: 10pt arial"><b>From:</b> <a title= =3D"wdleonard@gmail.com" onclick=3D"return top.js.OpenExtLink(window,event,= this)" href=3D"mailto:wdleonard@gmail.com" target=3D"_blank">David Leonard<= /a> </div> <div style=3D"FONT: 10pt arial"><b>To:</b> <a title=3D"flyrotary@lancaironl= ine.net" onclick=3D"return top.js.OpenExtLink(window,event,this)" href=3D"m= ailto:flyrotary@lancaironline.net" target=3D"_blank">Rotary motors in aircr= aft</a> </div></span> <div><span class=3D"e" id=3D"q_1062743b0ab9a901_4"> <div style=3D"FONT: 10pt arial"><b>Sent:</b> Monday, September 05, 2005 12:= 57 PM</div> <div style=3D"FONT: 10pt arial"><b>Subject:</b> [FlyRotary] Re: Another gre= at flying day =3D another day of troubleshooting</div> <div><br> </div> <div> <blockquote class=3D"gmail_quote" style=3D"PADDING-LEFT: 1ex; MARGIN: 0px 0= px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid"> <blockquote dir=3D"ltr" style=3D"PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MAR= GIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"> <p> Actually, Dave you had a higher pressure ratio (manifold to ambien= t) at 10,000 feet with 26" boost than at sea level with 36". = ; At sea level the pressure ratio would be 36/29.92 =3D 1.20. At 10,0= 00 ft ambient pressure =3D=20 20.57 " hg , so the pressure ratio would be 26/20= .57 =3D 1.26. Not much greater, but it was higher by approx.1.23"= ; Hg. (1.20 -1.26 =3D .06 *20.57 =3D 1.234" Hg). </p> <p><font face=3D"Arial">Ed A</font></p></blockquote></blockquote></div>Righ= t. But what does the plug know about the ambient pressure? I th= ought that it was just the absolute density of the charge that was contribu= ting to SAG.=20 <br><br>-- <br>Dave Leonard<br>Turbo Rotary RV-6 N4VY<br><a onclick=3D"retu= rn top.js.OpenExtLink(window,event,this)" href=3D"http://members.aol.com/_h= t_a/rotaryroster/index.html" target=3D"_blank">http://members.aol.com/_ht_a= /rotaryroster/index.html </a><br><a onclick=3D"return top.js.OpenExtLink(window,event,this)" href=3D= "http://members.aol.com/_ht_a/vp4skydoc/index.html" target=3D"_blank">http:= //members.aol.com/_ht_a/vp4skydoc/index.html</a> </span></div></blockquote>= </blockquote> </div><br><br clear=3D"all"><br>-- <br>Dave Leonard<br>Turbo Rotary RV-6 N4= VY<br><a href=3D"http://members.aol.com/_ht_a/rotaryroster/index.html">http= ://members.aol.com/_ht_a/rotaryroster/index.html</a><br><a href=3D"http://m= embers.aol.com/_ht_a/vp4skydoc/index.html"> http://members.aol.com/_ht_a/vp4skydoc/index.html</a>=20 ------=_Part_23592_14011051.1125945581366--