Return-Path: Received: from [65.54.169.77] (HELO hotmail.com) by logan.com (CommuniGate Pro SMTP 4.1.3) with ESMTP id 2568236 for flyrotary@lancaironline.net; Thu, 04 Sep 2003 22:51:29 -0400 Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Thu, 4 Sep 2003 19:51:28 -0700 Received: from 65.137.51.88 by bay3-dav47.bay3.hotmail.com with DAV; Fri, 05 Sep 2003 02:51:28 +0000 X-Originating-IP: [65.137.51.88] X-Originating-Email: [lors01@msn.com] Reply-To: "Tracy Crook" From: "Tracy Crook" To: "Rotary motors in aircraft" References: Subject: Re: Higher stagging MAP results Date: Thu, 4 Sep 2003 22:53:33 -0400 Organization: Real World Solutions Inc. MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_005F_01C37337.5DF775C0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 Message-ID: X-OriginalArrivalTime: 05 Sep 2003 02:51:28.0829 (UTC) FILETIME=[9AD236D0:01C37358] This is a multi-part message in MIME format. ------=_NextPart_000_005F_01C37337.5DF775C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MessageSpent about an hour flight testing the higher (~19" Hg MAP) = stagging point. For reference, keep in mind that it worked quite satisfactorily with it = set at ~14.5" Hg. The only drawback was that it had to be set up very = carefully around the stagging point to avoid a step in the mixture as = the throttle was moved through this point. Bottom line first: It works very well at 19", the main advantage being = that it makes setup much less critical at stagging point. I did it = while in-flight and it took about 10 - 15 min. total. This is a much = bigger deal for those running the big injectors like Rusty. (Other) Pros & cons: I normally cruise at an altitude of 12,000 - 14,000 feet. Manifold = pressure at economy cruise is 17 - 18" so this means the engine is = running on only the primaries now. Less wear & tear on the injectors? = Who knows / who cares? I'm still using my 17 year old injectors that = came on my original junk yard dog engine and they have yet to cause a = problem. Biggest 'problem' was the effect on the fuel flow instrument. I'm = currently using the one I designed that gets its input from the injector = duty cycle on one of the primary injectors. (circuit board courtesy of = Ed Anderson who neatly integrated it with a mixture monitor curcuit). = It is very accurate at cruise throttle settings after being calibrated. = Only down side is that it reads roughly double the fuel flow when = running on only the primary injectors due to the doubled pulse width = when below the stagging point. This didn't matter before because idle & = taxi was the only time the engine ran in stagged mode. Since I am now = running in stagged mode at cruise, the fuel flow now reads double the = actual flow. Bummer. Maybe I'll set the stagging to just below cruise = MAP instead of 19". Or ignore it until I get the prototype EM2 = installed which will happen soon. It knows when the EC2 is stagged and = compensates for this. Tracy ------=_NextPart_000_005F_01C37337.5DF775C0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message
Spent about an hour flight testing = the higher=20 (~19" Hg MAP) stagging point.
 
For reference, keep in mind that it = worked quite=20 satisfactorily with it set at ~14.5" Hg.  The only drawback was = that it had=20 to be set up very carefully around the stagging point to avoid = a step=20 in the mixture as the throttle was moved through this = point.
 
Bottom line first:  It works very = well at 19",=20 the main advantage being that it makes setup much less critical at = stagging=20 point.  I did it while in-flight and it took about 10 - 15 min.=20 total.  This is a much bigger deal for those running the big = injectors like=20 Rusty.
 
(Other) Pros & cons:
 
I normally cruise at an altitude of = 12,000 - 14,000=20 feet.  Manifold pressure at economy cruise is 17 - 18" so this = means the=20 engine is running on only the primaries now.  Less wear & tear = on the=20 injectors?  Who knows / who cares?  I'm still using my 17 year = old=20 injectors that came on my original junk yard dog engine and they have = yet to=20 cause a problem.
 
Biggest 'problem' was the effect on the = fuel flow=20 instrument.  I'm currently using the one I designed that gets its = input=20 from the injector duty cycle on one of the primary injectors.  = (circuit=20 board courtesy of Ed Anderson who neatly integrated it with a mixture = monitor=20 curcuit).   It is very accurate at cruise throttle settings = after=20 being calibrated.  Only down side is that it reads roughly double = the fuel=20 flow when running on only the primary injectors due to the doubled pulse = width=20 when below the stagging point. This didn't matter before = because idle &=20 taxi was the only time the engine ran in stagged mode.   Since = I am=20 now running in stagged mode at cruise, the fuel flow now = reads double=20 the actual flow.  Bummer.   Maybe I'll set the stagging = to just=20 below cruise MAP instead of 19".   Or ignore it until I get = the=20 prototype EM2 installed which will happen soon.  It knows when the = EC2 is=20 stagged and compensates for this.
 
Tracy
 
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