X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from aspensprings.uwyo.edu ([129.72.10.32] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTPS id 3888725 for flyrotary@lancaironline.net; Fri, 16 Oct 2009 19:16:42 -0400 Received-SPF: none receiver=logan.com; client-ip=129.72.10.32; envelope-from=SBoese@uwyo.edu Received: from ponyexpress-ht1.uwyo.edu (ponyexpress-ht1.uwyo.edu [10.84.60.208]) by aspensprings.uwyo.edu (8.14.2/8.14.2) with ESMTP id n9GNG4rW024022 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO) for ; Fri, 16 Oct 2009 17:16:04 -0600 (MDT) (envelope-from SBoese@uwyo.edu) Received: from Boesexps (172.26.4.5) by uwmail.uwyo.edu (10.84.60.198) with Microsoft SMTP Server id 8.1.393.1; Fri, 16 Oct 2009 17:16:04 -0600 From: sboese To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Stoich A/F Ratio?? : [FlyRotary] Re: where's the missing power? Date: Fri, 16 Oct 2009 17:16:03 -0600 Message-ID: <96962CFFA79C44CDB1531BCBFA41F932@gg.uwyo.edu> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_005B_01CA4E84.56B12520" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 ------=_NextPart_000_005B_01CA4E84.56B12520 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Ed & Bill, =20 If I understand correctly from discussion with Tracy, the default value = of 128 for a MAP table value is what you would read directly from the data stream. The 128 is reported as zero on the EM3 with positive values indicating enrichment and negative values indicating leaning. Values of zero on the EM3 are values which have not been changed from the default. =20 Steve =20 =20 -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ed Anderson Sent: Friday, October 16, 2009 4:49 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Stoich A/F Ratio?? : [FlyRotary] Re: where's = the missing power? =20 Ok, I understand now Bill. I think Al answered your question on how far from 14.7:1 to 9:1 on his controller of his 3 rotor - That's the only information I am aware of about how much twisting of the manual mixture control it may take. I can simply state that with the mixture Knob at = 3:00 its too much fuel for my N/A turbo block - so I would say Al's = information sounds reasonable to me. =20 Unless Tracy has really changed things with the EC3, there are NO = manifold pressure values in any bins (columns of the table) - the manifold = pressure (when used) is converted into a "bin" pointer which points to the appropriate bin (numbered from 0 - 128) for that corresponding manifold pressure). That "bin" selected by the manifold pressure value of the = engine then contains a fuel factor value represented by the value (height) of = the bar in that bin. I believe Tracy's default value is 128 which = theoretically would give a 14.7:1 air/fuel ratio. Going above that value enriches the mixture and below leans it. =20 IF there are zeros for the values of any of the bins then that says = there is no Map correction Table (MCT) correction factor used for that bin. . = So if the values of zero are valid, I would assume that for those regions = the fuel needed must be derived solely from some other parameter - like RPM = with the manifold pressure value only acting as a switch (above below 13Hg = for example) But, if that is indeed the case then I'm still a bit surprised there are = no MCT values for rpm. =20 =20 =20 There is the possibility that somehow the MCT values for those bins were = set to zero accidentally, but as you so rightly surmised, only Tracy can = answer the question you have. =20 Ed =20 ------=_NextPart_000_005B_01CA4E84.56B12520 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Ed & Bill,

 

If I understand correctly from = discussion with Tracy, the default value of 128 for a MAP table value is what you = would read directly from the data stream.  The 128 is reported as zero on = the EM3 with positive values indicating enrichment and negative values = indicating leaning.  Values of zero on the EM3 are values which have not been = changed from the default.

 

Steve

 

 

-----Original = Message-----
From: Rotary motors in = aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ed Anderson
Sent: Friday, October 16, = 2009 4:49 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: = Stoich A/F Ratio?? : [FlyRotary] Re: where's the missing = power?

 

Ok, I understand = now Bill.  I think Al answered your question on how far from 14.7:1 to = 9:1 on his controller of his 3 rotor – That’s the only information = I am aware of about how much twisting of the manual mixture control it may = take.  I can simply state that with the mixture Knob at 3:00 its too much fuel = for my N/A turbo block – so I would say Al’s information sounds = reasonable to me.

 

Unless Tracy has = really changed things with the EC3, there are NO manifold pressure values in = any bins (columns of the table) – the manifold pressure (when used) is = converted into a “bin”  pointer which points to the appropriate = bin (numbered from 0 – 128) for that corresponding manifold = pressure).  That “bin” selected by the manifold pressure value of the = engine then contains a fuel factor value represented by the value (height) of = the bar in that bin.  I believe Tracy’s default value is 128 which theoretically would give a 14.7:1 air/fuel ratio.  Going above that = value enriches the mixture and below leans it.

 

 IF there = are zeros for the values  of any of the bins then that says there is no Map correction Table (MCT) correction factor used for that bin. .  So = if the values of zero are valid,  I would assume that for those regions = the fuel needed must be derived solely from some other parameter – like RPM = with the manifold pressure value only acting as a switch (above below 13Hg = for example)

But, if that is = indeed the case then I’m still a bit surprised there are no MCT values = for rpm. 

 

 

There is the = possibility that somehow the MCT values for those bins were set to zero = accidentally, but as you so rightly surmised, only Tracy can answer the question you = have.

 

Ed<= /p>

 

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