X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 19 Oct 2009 09:18:42 -0400 Message-ID: X-Original-Return-Path: Received: from mailrelay.embarq.synacor.com ([208.47.184.3] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTP id 3890709 for lml@lancaironline.net; Mon, 19 Oct 2009 07:06:59 -0400 Received-SPF: pass receiver=logan.com; client-ip=208.47.184.3; envelope-from=liegner@embarqmail.com X-Original-Return-Path: X-BINDING: X-Spam-Rating: None X_CMAE_Category: 0,0 Undefined,Undefined X-CNFS-Analysis: v=1.0 c=1 a=lJyfCXToberWN9h6hM0A:9 a=y25WXFUsyLh22weq5sEA:7 a=jTkeTi6ikoNRpL5D8_x0Fj_1kbMA:4 X-CM-Score: 0 X-Scanned-by: Cloudmark Authority Engine Authentication-Results: smtp02.embarq.synacor.com smtp.user=liegner@embarqmail.com; auth=pass (LOGIN) Received: from [65.41.245.120] ([65.41.245.120:20207] helo=[172.16.1.2]) by mailrelay.embarq.synacor.com (envelope-from ) (ecelerity 2.2.2.40 r(29895/29896)) with ESMTPA id 94/E2-06485-1384CDA4; Mon, 19 Oct 2009 07:06:25 -0400 Mime-Version: 1.0 X-Sender: liegner@embarqmail.com@pop.embarqmail.com X-Original-Message-Id: In-Reply-To: References: X-Original-Date: Mon, 19 Oct 2009 07:01:40 -0400 X-Original-To: Isaac Heizer From: "Jeffrey Liegner, MD" Subject: Re: LOP MP setting for TSIO-550E X-Original-Cc: "Lancair Mailing List" Content-Type: text/plain; charset="us-ascii" ; format="flowed" 13.7 hp/gph for TSIO-550E 17.5 gph 240 HP = 68% (roughly) At 20gph ROP, you were sending 2.5 gallons per hour of 100LL out the exhaust manifold (unused). 14% greater carbon footprint without any benefit. Now try 34" 2500 18.0gph which is where I run often. Notice cyl 5 is hottest. Ususally it's cyl 2. Do you have the small rectangular cut opening in front of cyl 5? Jeff L LIVP >In the original email, i asked what MP one should use when running >LOP. George Braly suggested i go out and find out for myself. So I >did. > >Here are two runs, both LOP at 2500 RPM and 17.5 GPH lean of peak: > >30" MAP >EGT 1558 1558 1576 1563 1528 1484 >CHT 330 328 332 328 340 324 >TIT 1593 / 1634 > >31.6 MAP >EGT 1542 1544 1556 1540 1514 1472 >CHT 326 322 326 324 326 314 >TIT 1578 / 1611 > >The IAS in both cases was the same, so the horsepower must have been >the same. As one can see, higher MP means cooler temperatures. >Which makes sense, since the mixture is leaner. I think I'm >concluding that one sets the fuel flow to pick the horsepower >desired, and then adjusts the MP to get the temperature desired >(within reason). > >I thought 17.5 LOP would be about 75% power. So I went ROP and >reduced MP until i got the same IAS as the LOP runs above. It took >27" MAP and 20 GPH to match the IAS, which I think is about 65% >power (don't know why it isn't 75%...) > >-isaac >N7842K ES-P