X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [201.225.225.169] (HELO cwpanama.net) by logan.com (CommuniGate Pro SMTP 5.0c2) with ESMTP id 712006 for flyrotary@lancaironline.net; Mon, 05 Sep 2005 17:07:15 -0400 Received-SPF: none receiver=logan.com; client-ip=201.225.225.169; envelope-from=rijakits@cwpanama.net Received: from [201.224.93.110] (HELO usuarioq3efog0) by frontend3.cwpanama.net (CommuniGate Pro SMTP 4.2.10) with SMTP id 47392240 for flyrotary@lancaironline.net; Mon, 05 Sep 2005 16:13:23 -0500 Message-ID: <003501c5b25d$9191c7c0$6e5de0c9@usuarioq3efog0> From: "rijakits" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Another great flying day = another day of troubleshooting Date: Mon, 5 Sep 2005 16:05:38 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0031_01C5B233.A857A6C0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1437 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1441 This is a multi-part message in MIME format. ------=_NextPart_000_0031_01C5B233.A857A6C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Sorry Ed! I answered a previous message before reading this one! :)) Thomas J. ----- Original Message ----- From: Ed Anderson To: Rotary motors in aircraft Sent: Monday, September 05, 2005 3:11 PM Subject: [FlyRotary] Re: Another great flying day = another day of troubleshooting You're absolutely correct. The pressure ratio has nothing to do with MAP. I knew I should have had a second cup of coffee this morning. Back to trying to get a graphical LCD to work - hopefully with more success than encountered on this topic {:>) Duh! Ed ----- Original Message ----- From: David Leonard To: Rotary motors in aircraft Sent: Monday, September 05, 2005 2:39 PM Subject: [FlyRotary] Re: Another great flying day = another day of troubleshooting 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 :-) Dave On 9/5/05, Ed Anderson wrote: Well, actually it is absolute pressure that the spark plug is reacting to. In this example, the absolute pressure in the 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 facing a tougher task at 10,000 than at Sea level (in this example). Ed ----- Original Message ----- From: David Leonard To: Rotary motors in aircraft Sent: Monday, September 05, 2005 12:57 PM Subject: [FlyRotary] Re: Another great flying day = another day of troubleshooting Actually, Dave you had a higher pressure ratio (manifold to ambient) at 10,000 feet with 26" boost than at sea level with 36". At sea level the pressure ratio would be 36/29.92 = 1.20. At 10,000 ft ambient pressure = 20.57 " hg , so the pressure ratio would be 26/20.57 = 1.26. Not much greater, but it was higher by approx.1.23" Hg. (1.20 -1.26 = .06 *20.57 = 1.234" Hg). Ed A Right. But what does the plug know about the ambient pressure? I thought that it was just the absolute density of the charge that was contributing to SAG. -- 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 -- 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 ------=_NextPart_000_0031_01C5B233.A857A6C0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Sorry Ed!
 
I answered a previous message before reading = this one!=20 :))
 
Thomas J.
----- Original Message -----
From:=20 Ed=20 Anderson
Sent: Monday, September 05, = 2005 3:11=20 PM
Subject: [FlyRotary] Re: = Another great=20 flying day =3D another day of troubleshooting

You're absolutely correct. The pressure = ratio has=20 nothing to do with MAP.   I knew I should have had a second = cup of=20 coffee this morning.   Back to trying to get a graphical LCD = to work=20 - hopefully with more success than encountered on this topic {:>)=20 Duh!
 
Ed
 
----- Original Message -----
From:=20 David=20 Leonard
To: Rotary motors in = aircraft=20
Sent: Monday, September 05, = 2005 2:39=20 PM
Subject: [FlyRotary] Re: = Another great=20 flying day =3D another day of troubleshooting

Ed I am talking MAP in both cases.  I don't see how 26" = MAP is=20 higher than 36"MAP.  But I learned the old math  :-)
 
Dave

 
On 9/5/05, Ed=20 Anderson <eanderson@carolina.rr.com&g= t;=20 wrote:=20
Well, actually it is absolute pressure = that the=20 spark plug is reacting to.  In this example, the absolute = pressure in=20 the intake is 1.234" HG higher at 10,000 with your 26 " boost than = at sea=20 level with your 36" of boost..  This would contribute to an = increased=20 pressure in the combustion chamber when it is compressed over the = sea=20 level compression pressure.  Therefore, the spark plug is = facing a=20 tougher task at 10,000 than at Sea level (in this example).=20
 
Ed
----- Original Message ----- =
From: David = Leonard
To: Rotary motors in=20 aircraft
Sent: Monday, September = 05, 2005=20 12:57 PM
Subject: [FlyRotary] Re: = Another=20 great flying day =3D another day of troubleshooting

 

 Actually, Dave you had a higher pressure ratio = (manifold to=20 ambient) at 10,000 feet with 26" boost than at sea level = with=20 36".  At sea level the pressure ratio would be 36/29.92 = =3D=20 1.20.  At 10,000 ft ambient pressure =3D 20.57 " hg , = so the=20 pressure ratio would  be 26/20.57 =3D = 1.26. =20 Not much greater, but it was higher by approx.1.23" Hg. = (1.20 -1.26=20 =3D .06 *20.57 =3D 1.234" Hg).

Ed=20 A

Right.  But = what does=20 the plug know about the ambient pressure?  I thought that = it was=20 just the absolute density of the charge that was contributing to = SAG.=20

--
Dave Leonard
Turbo Rotary RV-6 N4VY
http://members.aol.com/_ht_a/rotaryroster/index.html=20
http://members.aol.com/_ht_a/vp4skydoc/index.html=20



--=20
Dave Leonard
Turbo Rotary RV-6 N4VY
http://memb= ers.aol.com/_ht_a/rotaryroster/index.html
http://members= .aol.com/_ht_a/vp4skydoc/index.html=20 ------=_NextPart_000_0031_01C5B233.A857A6C0--