X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml Date: Thu, 01 Feb 2007 00:59:52 -0500 Message-ID: X-Original-Return-Path: Received: from elasmtp-banded.atl.sa.earthlink.net ([209.86.89.70] verified) by logan.com (CommuniGate Pro SMTP 5.1.5) with ESMTP id 1803318 for lml@lancaironline.net; Wed, 31 Jan 2007 23:59:07 -0500 Received-SPF: none receiver=logan.com; client-ip=209.86.89.70; envelope-from=rtitsworth@mindspring.com DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=mindspring.com; b=KYG9LuOsQ1MYRJIQTMxNoKomMcJAGoo+0ZcEfJF2NQirLfd2rORem7lwL5ZnzSgY; h=Received:From:To:Subject:Date:Message-ID:MIME-Version:Content-Type:X-Mailer:Thread-Index:In-Reply-To:X-MimeOLE:X-ELNK-Trace:X-Originating-IP; Received: from [69.3.251.97] (helo=RDTVAIO) by elasmtp-banded.atl.sa.earthlink.net with asmtp (Exim 4.34) id 1HCU1c-0004Nd-HA for lml@lancaironline.net; Wed, 31 Jan 2007 23:58:20 -0500 From: "rtitsworth" X-Original-To: "'Lancair Mailing List'" Subject: RE: [LML] Re: Altitude Switch -- how's a guy to know? X-Original-Date: Wed, 31 Jan 2007 23:58:14 -0500 X-Original-Message-ID: <006501c745bd$94a698b0$84affea9@RDTVAIO> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0066_01C74593.ABD090B0" X-Mailer: Microsoft Office Outlook 11 Thread-Index: AcdFhxbfjaOyB8OuRYOp6B5CJSXbeQAM8Hrg In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3028 X-ELNK-Trace: b17f11247b2ac8f0a79dc4b33984cbaa0a9da525759e26541847e9c6ee89efe57c10d7f136d1fb7730febb85a5f48815350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 69.3.251.97 This is a multi-part message in MIME format. ------=_NextPart_000_0066_01C74593.ABD090B0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit If your MR2 is like most autos it uses an O2 sensor in the exhaust as part of a feedback loop to dynamically adjust mixture (timed injector pulses) via the ECU (engine control unit/computer). It also uses a mass airflow sensor up front as part of that automatic mixture control process. Thus in the automotive case, fuel pressure is not really critical (as long as it is in the appropriate range to cause atomization from the nozzle), since the ECU controls mixture via electrical fuel injector pulse timing (it also controls spark timing). The whole system is actually quite sophisticated to enable maximizing, horsepower, durability, and economy, while also minimizing emissions, and it could easily adjust for 26,000ft and/or M60F, but it's only practical due to spreading the development/testing cost over large auto production volumes. The down side is if anything goes wrong, it can easily just stop. My new Chevy Suburban was dead on the side of the road, when a $5 crank position sensor went south. Luckily, it's way too heavy to get off the ground in the first place {grin}. Rick _____ From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of VTAILJEFF@aol.com Sent: Wednesday, January 31, 2007 5:28 PM To: lml Subject: [LML] Re: Altitude Switch -- how's a guy to know? In a message dated 1/31/2007 3:46:02 PM Central Standard Time, marv@lancaironline.net writes: For further comparison, the engine in my Toyota MR2 hasn't run noticeabley rich or lean for the last 175,000 miles. There has been no service of the fuel system for 17 years. But has your Toyota operated at FL 260 or in minus 60 degrees F, lately? (that is why your Toyota is not a good comparison) Jeff ------=_NextPart_000_0066_01C74593.ABD090B0 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

If your MR2 is like most autos it = uses an O2 sensor in the exhaust as part of a feedback loop to dynamically = adjust mixture (timed injector pulses) via the ECU (engine control = unit/computer).  It also uses a mass airflow sensor up front as part of that automatic = mixture control process.  Thus in the automotive case, fuel pressure is not really critical (as long as it is in the appropriate range to cause atomization = from the nozzle), since the ECU controls mixture via electrical fuel injector = pulse timing (it also controls spark timing).  The whole system is = actually quite sophisticated to enable maximizing, horsepower, durability, and = economy, while also minimizing emissions, and it could easily adjust for 26,000ft = and/or M60F, but it’s only practical due to spreading the development/testing = cost over large auto production volumes.

 

The down side is if anything goes = wrong, it can easily just stop.  My new Chevy Suburban was dead on the = side of the road, when a $5 crank position sensor went south.  Luckily, = it’s way too heavy to get off the ground in the first place = {grin}.

 

Rick

 

From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of = VTAILJEFF@aol.com
Sent: Wednesday, January 31, 2007 5:28 PM
To: lml
Subject: [LML] Re: Altitude Switch = -- how's a guy to know?

 

In a message dated 1/31/2007 = 3:46:02 PM Central Standard Time, marv@lancaironline.net writes:

For further comparison, the engine in my Toyota MR2 hasn't run
   noticeabley rich or lean for the last 175,000 miles.
   There has been no service of the fuel system for 17 = years.

But has your Toyota operated at FL 260 or in = minus 60 degrees F, lately? (that is why your Toyota is not a good comparison)

 

=

Jeff

 

=

 

=
------=_NextPart_000_0066_01C74593.ABD090B0--