X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 09 Jan 2008 09:13:19 -0500 Message-ID: X-Original-Return-Path: Received: from ironport5.liveoakmail.com ([216.110.12.21] verified) by logan.com (CommuniGate Pro SMTP 5.2c4) with ESMTP id 2636879 for lml@lancaironline.net; Tue, 08 Jan 2008 20:10:10 -0500 Received-SPF: none receiver=logan.com; client-ip=216.110.12.21; envelope-from=walter@advancedpilot.com X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AgAAAA+tg0dAMf4VgGdsb2JhbACCb40tAQENFZkt X-IronPort-AV: E=Sophos;i="4.24,259,1196661600"; d="scan'208,217";a="41742665" Received: from rs5.liveoakhosting.com (HELO secure5.liveoakhosting.com) ([64.49.254.21]) by ironport5.liveoakmail.com with ESMTP; 08 Jan 2008 19:09:31 -0600 Received: (qmail 31634 invoked from network); 8 Jan 2008 19:09:30 -0600 Received: from ip68-108-233-192.br.br.cox.net (HELO ?10.0.1.4?) (68.108.233.192) by rs5.liveoakhosting.com with (AES128-SHA encrypted) SMTP; 8 Jan 2008 19:09:30 -0600 Mime-Version: 1.0 (Apple Message framework v753) In-Reply-To: References: Content-Type: multipart/alternative; boundary=Apple-Mail-2-342953404 X-Original-Message-Id: <204C478C-2EA4-426E-809E-EA218BEEEC6C@advancedpilot.com> From: Walter Atkinson Subject: Re: [LML] Re: One mag, One electronic ignition X-Original-Date: Tue, 8 Jan 2008 19:09:29 -0600 X-Original-To: "Lancair Mailing List" X-Mailer: Apple Mail (2.753) --Apple-Mail-2-342953404 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Mark: I think what is happening is that the thetaPP is changed less by the loss of the mag than by the loss of the EI. This had little to do with the amount of fuel being burned. BTW, I just looked at the thetaPP data on a set-up where the timing was changed by as little as 2 degrees, advanced. The thetaPP was advanced to 10dATDC and the peak pressures were above 1100 psi. This is not a good thing. You guys do as you please, but that's not something I want to do to my engine. Spark plugs begin to be blasted out of cylinders at 1200psi--by imperical experience. These are observations of hard data. Walter On Jan 8, 2008, at 2:23 PM, Mark Ravinski wrote: Hi Walter, When one shuts off the mag and runs on the EI, (during cruise), there is some small increase in EGT and decrease in CHT. Then when one shuts off the EI and runs on the mag alone, there is a much more dramatic shift in the same direction as before. I believe that the vacuum advanced EI is doing a much better job of burning more of the fuel in the cylinder. (again, at reduced power settings where we spend most of out time and fuel (assuming normally aspirated.)) I've used three different brands of EI's and have had similar results in this regard. Please don't ask for hard data - I only have observations. Mark Ravinski ----- Original Message ----- From: Walter Atkinson To: lml@lancaironline.net Sent: Monday, January 07, 2008 3:51 PM Subject: [LML] Re: One mag, One electronic ignition How does that become evident? Please explain. Walter On Jan 7, 2008, at 10:31 AM, Mark Ravinski wrote: Also, a common test is to shut off each system alternately and look at CHT and EGT. It becomes evident that the EI is burning more of the fuel in the cylinder and the straight mag is burning more of the fuel in the exhaust header. --Apple-Mail-2-342953404 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=ISO-8859-1 Mark:

I think what = is happening is that the thetaPP is changed less by the loss of the mag = than by the loss of the EI. =A0This had little to do with the amount of = fuel being burned.

BTW, I just looked at the = thetaPP data on a set-up where the timing was changed by as little as 2 = degrees, advanced. =A0The thetaPP was advanced to 10dATDC and the peak = pressures were above 1100 psi. =A0This is not a good thing. =A0You guys = do as you please, but that's not something I want to do to my engine. = =A0Spark plugs begin to be blasted out of cylinders at 1200psi--by = imperical experience.

These are observations of = hard data.

Walter


On Jan 8, = 2008, at 2:23 PM, Mark Ravinski wrote:

Hi Walter,
When one shuts off the mag and runs on the EI, (during = cruise), there is some small increase in EGT and decrease in CHT.=A0 = Then when one shuts off the EI and runs on the mag alone, there is a = much more dramatic shift in the same direction as = before.
I believe that = the vacuum advanced EI is doing a much better job of burning more of the = fuel in the cylinder.=A0 (again, at reduced power settings where we = spend most of out time and fuel (assuming normally = aspirated.))
I've used three different brands of EI's and = have had similar results in this regard.
Please don't ask for hard data - I only have = observations.
=A0
Mark = Ravinski
----- = Original Message -----
=A0Monday, = January 07, 2008 3:51 PM
Subject:=A0[LML] Re: One mag, One = electronic ignition

How does that become evident? = =A0Please explain.

Walter


On Jan 7, = 2008, at 10:31 AM, Mark Ravinski wrote:

Also, a common test is to shut off each system = alternately and look at CHT and EGT.=A0 It becomes evident that the EI = is burning more of the fuel in the cylinder and the straight mag is = burning more of the fuel in the exhaust = header.



= --Apple-Mail-2-342953404--