Return-Path: Received: from pop3.olsusa.com ([63.150.212.2] verified) by logan.com (CommuniGate Pro SMTP 3.5.1) with ESMTP id 999652 for rob@logan.com; Sat, 29 Dec 2001 12:32:27 -0500 Received: from femail8.sdc1.sfba.home.com ([24.0.95.88]) by pop3.olsusa.com (Post.Office MTA v3.5.3 release 223 ID# 0-71866U8000L800S0V35) with ESMTP id com for ; Sat, 29 Dec 2001 12:18:36 -0500 Received: from cc1860069a ([67.164.204.130]) by femail8.sdc1.sfba.home.com (InterMail vM.4.01.03.20 201-229-121-120-20010223) with SMTP id <20011229171931.XWWQ16621.femail8.sdc1.sfba.home.com@cc1860069a> for ; Sat, 29 Dec 2001 09:19:31 -0800 Message-ID: <01bf01c1908c$ff24af60$82cca443@roylok1.mi.home.com> From: "Edmond de Chazal" To: References: <20011228052429.AAA19477@pop3.olsusa.com> Subject: Re: LOP question Date: Sat, 29 Dec 2001 12:19:38 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Mailing-List: lancair.list@olsusa.com Reply-To: lancair.list@olsusa.com <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> Hi George, I thought Carl was being a bit conservative, on the other he hasn't crashed yet causing insurance rates to go up..... . I'm a 360 driver with an IO360-B1F and have lately been practicing your recommendations for leaning, including the 'big pull' you told Brent about awhile ago. It really works well. I pull the mixture back until stumbling or power loss starts then I richen for smoothness. Just like the simple carbureted airplanes I used to fly. Doing this causes me to operate at about Peak. The CHTs drop well below where they would be when I used to operate at 150 ROP. I add/subtract manifold pressure to get the target fuel flow which relates to %power using the Lycoming manual graphs for Best Economy which they stipulate as at Peak EGT. I used your downloaded data sheets and ran the test 3 times to examine my cylinder spread. I got a consistent 0.5 gph spread with the cylinders 2 and 3 being the first ones to peak at about 8.2 gph. for the test settings. Roughness would set in between 25 and 45 degrees lean of first cylinder to peak depending on the test run. Unfortunately, the EGT resolution on the Vision Microsystems VMS-1000 unit is only 8 degrees or there abouts (confirmed with VM guy) so the data's not as smooth as I'd like. My early temperature problems seem to have been most effectively reduced by 1: operating at Peak or LOP and by 2: using unfiltered ram air on takeoff so that the cylinders are not starved for cooling air from the baffle mounted air intake filter. Question: The fuel flows on WOT climb from sea level are enormous - as high as 17 gph - so I'm wondering why I shouldn't lean during climb to reduce these while keeping the CHTs in a comfortable range. I climb out at about 140 kts typically. I'm burning 100LL. Regards, Ed de Chazal >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML website: http://members.olsusa.com/mkaye/maillist.html LML Builders' Bookstore: http://www.buildersbooks.com/lancair Please remember that purchases from the Builders' Bookstore assist with the management of the LML. Please send your photos and drawings to marvkaye@olsusa.com. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>