X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from ms-smtp-03.southeast.rr.com ([24.25.9.102] verified) by logan.com (CommuniGate Pro SMTP 5.1c.4) with ESMTP id 1414964 for flyrotary@lancaironline.net; Fri, 22 Sep 2006 08:57:37 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.102; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-100-038.carolina.res.rr.com [24.74.100.38]) by ms-smtp-03.southeast.rr.com (8.13.6/8.13.6) with SMTP id k8MCusPM011973 for ; Fri, 22 Sep 2006 08:56:55 -0400 (EDT) Message-ID: <001401c6de46$beb137c0$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Fuel Pressure Regulator Vacuum or Boost?? Date: Fri, 22 Sep 2006 08:58:04 -0400 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=response Content-Transfer-Encoding: 7bit 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 X-Virus-Scanned: Symantec AntiVirus Scan Engine Thanks, Buly. Sounds like your pressure regulator is both vacuum and boost referenced. Do you have a part/model number handy? Ed ----- Original Message ----- From: "Bulent Aliev" To: "Rotary motors in aircraft" Sent: Thursday, September 21, 2006 9:34 PM Subject: [FlyRotary] Re: Fuel Pressure Regulator Vacuum or Boost?? > Ed, my FPR is from Aeromotive and it is MP referenced. The FP is lowest > at idle and than starts climbing with rise of MP. > Bulent "Buly" Aliev > FXE Ft lauderdale, FL > http://tinyurl.com/s5xw8 > > On Sep 21, 2006, at 1:57 PM, Ed Anderson wrote: > >> For the entire life of my rotary powered RV-6A, I have flown with a >> "Boost Referenced" adjustable fuel pressure regulator from MSD. As you >> know, it is desirable to keep the pressure differential between the >> injector fuel rail pressure and the manifold pressure a constant for >> best fuel injection control. >> >> I flew for several years thinking that since my pressure regulator was >> manifold reference that it was indeed doing this. Then the light bulb >> came on - my fuel pressure holds rock-steady at 43 PSI - and does not >> vary between idle and WOT! This certainly implies that the fuel >> pressure IS NOT varying as a function of manifold pressure. >> >> Then doing some recent research on fuel pressure regulators, I noticed >> that some say they are "Boost Referenced" and other's say "Vacuum/Boost >> Referenced". My conclusion (which may be incorrect) is that while my >> pressure regulator is "Boost Referenced" it is not "Vacuum Referenced". >> The difference (If I understand it correctly ) is that my regulator >> would increase fuel pressure IF it ever encounter manifold pressure >> greater than ambient - since I am not used forced induction that never >> happens - which in turn appears to be the reason I never see the fuel >> pressure changing in response to manifold "vacuum". >> >> So my question to those who realllllllyyyyyy know - is it correct that >> for my NA 13B I need a fuel pressure regulator that responses to >> manifold "Vacuum" or is the difference in description between "vacuum >> referenced and boost referenced " just semantics in advertising? >> >> Thanks >> >> Ed >> >> Ed Anderson >> Rv-6A N494BW Rotary Powered >> Matthews, NC >> eanderson@carolina.rr.com >> http://members.cox.net/rogersda/rotary/configs.htm#N494BW >> > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ >