X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [201.225.225.167] (HELO cwpanama.net) by logan.com (CommuniGate Pro SMTP 5.1c.4) with ESMTP id 1414355 for flyrotary@lancaironline.net; Thu, 21 Sep 2006 23:20:04 -0400 Received-SPF: none receiver=logan.com; client-ip=201.225.225.167; envelope-from=rijakits@cwpanama.net Received: from [201.224.93.110] (HELO usuario5ebe209) by frontend1.cwpanama.net (CommuniGate Pro SMTP 4.2.10) with SMTP id 79610849 for flyrotary@lancaironline.net; Thu, 21 Sep 2006 22:58:23 -0500 Message-ID: <007001c6ddf5$e11c1d80$6e5de0c9@usuario5ebe209> From: "Thomas y Reina Jakits" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Fuel Pressure Regulator Vacuum or Boost?? Date: Thu, 21 Sep 2006 22:19:13 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_006D_01C6DDCB.F7C7BDC0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2962 This is a multi-part message in MIME format. ------=_NextPart_000_006D_01C6DDCB.F7C7BDC0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Ignorant Question: a) Does Tracy's system need/use manifold referenced fuel-pressure? b) If not shouldn't the fuel pressure stay constant (absolute), so that = the electronic control takes care of mixture with a fixed fuel pressure = and adjusts injector pulse according to manifold pressure? c) What advantage would you have in a system where the fuel is manifold = referenced directly? It still is controlled by the pulse width.... Andvanced thanx for enlightening me! Thomas J. ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Thursday, September 21, 2006 3:26 PM Subject: [FlyRotary] Re: Fuel Pressure Regulator Vacuum or Boost?? Thanks, Bill, for confirming my suspicion. The 9 year old regulator I = am using was purchased because it had a manifold reference line and was = listed as a regulator for boost. I assumed (wrongly it appears) that = because it was referenced to the manifold that it would adjust fuel = pressure for manifold "vacuum" as well as positive boost. =20 After noting that some pressure regulators were for "Boost" and others = for "Vacuum/Boost" I came to suspect that the difference was not just = semantics in advertising. But, wanted someone who realllllyyyy knew to = put me straight. Ed ----- Original Message -----=20 From: wrjjrs@aol.com=20 To: Rotary motors in aircraft=20 Sent: Thursday, September 21, 2006 3:42 PM Subject: [FlyRotary] Re: Fuel Pressure Regulator Vacuum or Boost?? Ed, You are correct, the "boost reference" is only changed at more than = 1 atmosphere. The usually more expensive vacuum and boost referenced = unit would lower the pressure at idle. Bill Jepson=20 =20 -----Original Message----- From: joeh@pilgrimtech.com To: flyrotary@lancaironline.net Sent: Thu, 21 Sep 2006 11:48 AM Subject: [FlyRotary] Re: Fuel Pressure Regulator Vacuum or Boost?? I presume your pressure gauge remains steady as you adjust throttle = ? Yep, no real change in FP over the entire range from idle to WOT. Joe Hull Cozy Mk-IV N31CZ (65 hrs - Rotary 13B NA)=20 Redmond (Seattle), Washington -------------------------------------------------------------------------= --- Check out the new AOL. Most comprehensive set of free safety and = security tools, free access to millions of high-quality videos from = across the web, free AOL Mail and more. ------=_NextPart_000_006D_01C6DDCB.F7C7BDC0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Ignorant Question:
 
a) Does Tracy's system need/use manifold = referenced=20 fuel-pressure?
b) If not shouldn't the fuel pressure stay = constant=20 (absolute), so that the electronic control takes care of mixture with a = fixed=20 fuel pressure and adjusts injector pulse according to manifold=20 pressure?
c) What advantage would you have in a system = where the=20 fuel is manifold referenced directly? It still is controlled by the = pulse=20 width....
 
Andvanced thanx for enlightening = me!
 
Thomas J.
----- Original Message -----
From:=20 Ed=20 Anderson
Sent: Thursday, September 21, = 2006 3:26=20 PM
Subject: [FlyRotary] Re: Fuel = Pressure=20 Regulator Vacuum or Boost??

Thanks, Bill, for confirming my = suspicion. =20 The 9 year old regulator I am using was purchased because it had a = manifold=20 reference line  and was listed as a regulator for boost.  I = assumed=20 (wrongly it appears) that because it was referenced to the manifold = that it=20 would adjust fuel pressure for manifold "vacuum" as well as positive=20 boost. 
 
After noting that some pressure = regulators were=20 for "Boost" and others for "Vacuum/Boost" I came to suspect that the=20 difference was not just semantics in advertising.  But, wanted = someone=20 who realllllyyyy knew to put me straight.
 
Ed
----- Original Message -----
From:=20 wrjjrs@aol.com=20
To: Rotary motors in = aircraft=20
Sent: Thursday, September 21, = 2006 3:42=20 PM
Subject: [FlyRotary] Re: Fuel = Pressure=20 Regulator Vacuum or Boost??

Ed,
 You are correct, the "boost reference" is only changed at = more=20 than 1 atmosphere. The usually more expensive vacuum and boost = referenced=20 unit would lower the pressure at idle.
Bill Jepson 
 
 
-----Original Message-----
From: joeh@pilgrimtech.com
To: = flyrotary@lancaironline.net
Sent:=20 Thu, 21 Sep 2006 11:48 AM
Subject: [FlyRotary] Re: Fuel Pressure=20 Regulator Vacuum or Boost??

I presume your = pressure gauge=20 remains steady as you adjust throttle ?
 
Yep, no = real change=20 in FP over the entire range from idle to WOT.
 
Joe Hull
Cozy Mk-IV N31CZ (65 hrs - = Rotary 13B=20 NA)
Redmond (Seattle),=20 Washington
Check out the new AOL. Most comprehensive = set of=20 free safety and security tools, free access to millions of = high-quality=20 videos from across the web, free AOL Mail and=20 more.
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