X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.2 cv=QoAc5h6d c=1 sm=1 tr=0 a=OOk3grDtseiBCbCVAyyo2Q==:117 a=29enrAnRItQSTk1fLlBiTQ==:17 a=7oIiURvLaKEA:10 a=17xQtuQ_ucwA:10 a=x7bEGLp0ZPQA:10 a=Fee85h93u3AA:10 a=R9QF1RCXAYgA:10 a=Ia-xEzejAAAA:8 a=ymAW3s8FzfqBgFWzVDgA:9 a=QEXdDO2ut3YA:10 a=I1v1RxDv0JwVGyia:21 a=Urk15JJjZg1Xo0ryW_k8:22 From: "Accountlehanover lehanover@aol.com" Received: from omr-a016e.mx.aol.com ([204.29.186.65] verified) by logan.com (CommuniGate Pro SMTP 6.2.6) with ESMTPS id 11455028 for flyrotary@lancaironline.net; Mon, 30 Jul 2018 15:06:01 -0400 Received-SPF: pass receiver=logan.com; client-ip=204.29.186.65; envelope-from=lehanover@aol.com Received: from mtaomg-maa01.mx.aol.com (mtaomg-maa01.mx.aol.com [172.26.222.143]) by omr-a016e.mx.aol.com (Outbound Mail Relay) with ESMTP id 624F038000B4 for ; Mon, 30 Jul 2018 15:05:45 -0400 (EDT) Received: from core-mda09b.mail.aol.com (core-mda09.mail.aol.com [172.27.39.9]) by mtaomg-maa01.mx.aol.com (OMAG/Core Interface) with ESMTP id 3402238000083 for ; Mon, 30 Jul 2018 15:05:45 -0400 (EDT) Received: from 71.67.186.114 by webjas-vad244.srv.aolmail.net (10.96.35.247) with HTTP (WebMailUI); Mon, 30 Jul 2018 15:05:45 -0400 Date: Mon, 30 Jul 2018 15:05:45 -0400 To: flyrotary@lancaironline.net Message-Id: <164ec94ff6e-c8d-15879@webjas-vad244.srv.aolmail.net> In-Reply-To: References: Subject: Re: [FlyRotary] Re: cooling MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_115063_1483421263.1532977545069" X-MB-Message-Source: WebUI X-MB-Message-Type: User X-Mailer: JAS DWEB X-Originating-IP: [71.67.186.114] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20150623; t=1532977545; bh=+ophhrUvXwqH5foY6bsE/kyOiJHO6IyiVwzdTprn4HQ=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=uTF40UGPpS+0DxuS3LWUYu3VZ8mMclqLW49josdkuMr1lZQeTXC2qraCouObI+XQy ddQcCJ9q0zwIYHeAc1wIUndjTAnbj7Qyow0MjJdKkXN4bRh3zNumZ12OjSzoyuqNT1 qPCAlS9C3f2OyjFs7/gEVCdcj4JBXoR4KUPAh85M= x-aol-sid: 3039ac1ade8f5b5f6189349d ------=_Part_115063_1483421263.1532977545069 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Generally not the case. Best power is between 12.5 air to fuel and 12.7 air= to fuel. So, the EGT for that range is at about 1600 degrees. So, if the p= robe is in too deep or is too close to the port face you will get a EGT num= ber that does not match the actual mixture ratio. A back up heated Oxygen s= ensor will be more accurate than an EGT gauge but more expensive. Both meas= ure mixture strength although the Oxygen sensor is newer. In olden times th= ere was only the EGT gauge.=C2=A0=20 The temp during combustion is what you want to know. So, the EGT tells you = the temp of gasses leaving the chamber, so we must speculate on the chamber= temps. Also the Oxygen quantity left in the exhaust flow allows us only to= guess at what the temps in the chamber might be. So, adding more fuel in h= opes of lowering EGT will run aground because there is always some extra Ox= ygen left in the flow which will raise the EGT When it unites with the adde= d fuel. =C2=A0 The airplane is just a Dyno with wings. So, fly at top speed (best power) a= nd lean to stumble then back rich to just smooth. The heated Oxygen sensor = should show about 12.5 to one. The EGT should show 1600 degrees.=C2=A0 At best speed. going for highest power. Once have that data. add a killer i= gnition and repeat going for lowest fuel flow.=C2=A0 This will get you the = mixture that is just short of best power. Now repeat, but once at best spee= d just add fuel and watch for a speed increase. This will get you above bes= t power . This will also get you into the highest=C2=A0chamber temps. So, j= ust sit there for a few seconds. Now you have best power slightly rich of p= eak and best power slightly lean of peak.=C2=A0 Temps come down with lean o= f peak operations because less fuel is being introduced. Lynn E. Hanover=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 .=C2=A0 =C2=A0 In a message dated 7/30/2018 3:47:13 AM Eastern Standard Time, flyrotary@la= ncaironline.net writes: =C2=A0 Lynn, =C2=A0=C2=A0=C2=A0=C2=A0 Interesting as the EGT can only be lowered by redu= cing power -- or am I mistaken??=C2=A0 The engines seem to be able to run a= t 1800 EGT plus, so I no longer worry.=C2=A0 Your thoughts???=C2=A0 Neil Un= ger. ------=_Part_115063_1483421263.1532977545069 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit
Generally not the case. Best power is between 12.5 air to fuel and 12.7 air to fuel. So, the EGT for that range is at about 1600 degrees. So, if the probe is in too deep or is too close to the port face you will get a EGT number that does not match the actual mixture ratio. A back up heated Oxygen sensor will be more accurate than an EGT gauge but more expensive. Both measure mixture strength although the Oxygen sensor is newer. In olden times there was only the EGT gauge.
The temp during combustion is what you want to know. So, the EGT tells you the temp of gasses leaving the chamber, so we must speculate on the chamber temps. Also the Oxygen quantity left in the exhaust flow allows us only to guess at what the temps in the chamber might be. So, adding more fuel in hopes of lowering EGT will run aground because there is always some extra Oxygen left in the flow which will raise the EGT When it unites with the added fuel.

The airplane is just a Dyno with wings. So, fly at top speed (best power) and lean to stumble then back rich to just smooth. The heated Oxygen sensor should show about 12.5 to one. The EGT should show 1600 degrees.
At best speed. going for highest power. Once have that data. add a killer ignition and repeat going for lowest fuel flow.  This will get you the mixture that is just short of best power. Now repeat, but once at best speed just add fuel and watch for a speed increase. This will get you above best power . This will also get you into the highest chamber temps. So, just sit there for a few seconds. Now you have best power slightly rich of peak and best power slightly lean of peak.  Temps come down with lean of peak operations because less fuel is being introduced.
Lynn E. Hanover          .

In a message dated 7/30/2018 3:47:13 AM Eastern Standard Time, flyrotary@lancaironline.net writes:

Lynn,

     Interesting as the EGT can only be lowered by reducing power -- or am I mistaken??  The engines seem to be able to run at 1800 EGT plus, so I no longer worry.  Your thoughts???  Neil Unger.

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