X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sun, 01 Nov 2009 19:01:41 -0500 Message-ID: X-Original-Return-Path: Received: from elasmtp-junco.atl.sa.earthlink.net ([209.86.89.63] verified) by logan.com (CommuniGate Pro SMTP 5.2.17) with ESMTP id 3911320 for lml@lancaironline.net; Sun, 01 Nov 2009 08:13:00 -0500 Received-SPF: none receiver=logan.com; client-ip=209.86.89.63; envelope-from=colyncase@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=q4pE5+iLCM/RGlsY7hHi7Y2jPAwJM2lUnu6Sads8YGqS0g9zpwHSqzUa1Gp38zj0; h=Received:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE:X-ELNK-Trace:X-Originating-IP; Received: from [216.57.118.63] (helo=ccaselt3) by elasmtp-junco.atl.sa.earthlink.net with esmtpa (Exim 4.67) (envelope-from ) id 1N4aEK-0002ea-Tl for lml@lancaironline.net; Sun, 01 Nov 2009 08:12:25 -0500 X-Original-Message-ID: <04d001ca5af4$f4401180$668c020a@nvidia.com> From: "Colyn Case at earthlink" X-Original-To: "Lancair Mailing List" References: Subject: Re: [LML] LOP operations with O-360 X-Original-Date: Sun, 1 Nov 2009 08:12:23 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_04CD_01CA5ACB.0A937FA0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3598 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3350 X-ELNK-Trace: 63d5d3452847f8b1d6dd28457998182d7e972de0d01da940cc521dc68b3d1f2df32d9f18dfa9e94c350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 216.57.118.63 This is a multi-part message in MIME format. ------=_NextPart_000_04CD_01CA5ACB.0A937FA0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Keith, I'd be focused on egt's not cht's as the main indicator of how = far LOP you are. Make sure you get past peak, other than that, cht's = below 400. Sounds like you have a very good installation. On my c172rg with an O-360 I can run just slightly lean of peak before = the vibration gets unreasonable. ...so I have the MP back to 21 or = less before going there. If I can get the cht's to < 390 I'm happy. Colyn ----- Original Message -----=20 From: Keith Smith=20 To: lml@lancaironline.net=20 Sent: Saturday, October 31, 2009 4:17 PM Subject: [LML] LOP operations with O-360 So, after reading John Deakin's articles upwards of 5 times, I'd been = itching to try lean of peak operations, but figured it was out of the = question without fuel injection, and quite possibly balanced injectors = at that. I then came across an update saying that someone had quite a bit of = luck with non-injected engine using carb heat, which supposedly helped = vaporize the fuel prior to entering the cylinders. So, up I went today. Being cautious of the rough transition zone, I = pulled through it pretty aggressively once it started happening, a = little too far, evidently, because the engine gave up. I figured that = might happen, but also figured the restart would be uneventful, = consisting of no more than gently pushing the mixture in until it fired = again). =20 My EGT's were around 1450 and the engine smooth as silk. Hmmm...had I = pushed too far, back over to ROP? It didn't feel like that was = possible, I'd barely inched the mixture forward. Fuel flow was around = 9.5. That would be normal for being up at 9/10k, but not down here at = 4k, with wide open throttle. Then I saw the CHT's. Oh baby. 320! Just to confirm, I edged the mixture in a tiny bit more, and sure = enough, the EGT's crept up 20degs. That confirmed, I was on the lean = side ever since the restart. Later on, I killed the carb heat, and while I could feel a TINY = different in vibration, it was not significant. Holy cow, it seems to run perfectly happily on the lean side, with an = O-360! Who knew?? With that VERY informal test out of the way, I will now become = well-versed with the lean finder mode on the engine monitor...today's = flight was just to find out if I should bother digging deeper. For a = 60-80deg drop in CHT's, and 9.5gph instead of 12gph (down low, least), = I'll take it! =20 I'm posting this for those that are interested in LOP, but haven't = tried it with non-injected power plants. Keith N360JH ------=_NextPart_000_04CD_01CA5ACB.0A937FA0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Keith, I'd be focused on egt's not = cht's as the=20 main indicator of how far LOP you are.  Make sure you get past = peak, other=20 than that, cht's below 400.
Sounds like you have a very good=20 installation.
On my c172rg with an O-360 I can run = just slightly=20 lean of peak before the vibration gets unreasonable.   ...so I = have=20 the MP back to 21 or less before going there.
If I can get the cht's to < 390 I'm=20 happy.
 
Colyn
----- Original Message -----
From:=20 Keith=20 Smith
Sent: Saturday, October 31, = 2009 4:17=20 PM
Subject: [LML] LOP operations = with=20 O-360

So, after reading John Deakin's articles upwards of 5 = times,=20 I'd been itching to try lean of peak operations, but figured it was = out of the=20 question without fuel injection, and quite possibly balanced injectors = at=20 that.

I then came across an update saying that someone had = quite a bit=20 of luck with non-injected engine using carb heat, which supposedly = helped=20 vaporize the fuel prior to entering the cylinders.

So, up I = went today.=20 Being cautious of the rough transition zone, I pulled through it = pretty=20 aggressively once it started happening, a little too far, evidently, = because=20 the engine gave up.  I figured that might happen, but also = figured the=20 restart would be uneventful, consisting of no more than gently pushing = the=20 mixture in until it fired again). 

My EGT's were around = 1450 and=20 the engine smooth as silk. Hmmm...had I pushed too far, back over to=20 ROP?  It didn't feel like that was possible, I'd barely inched = the=20 mixture forward.  Fuel flow was around 9.5.  That would be = normal=20 for being up at 9/10k, but not down here at 4k, with wide open = throttle. =20 Then I saw the CHT's. Oh baby.  320!

Just to confirm, I = edged the=20 mixture in a tiny bit more, and sure enough, the EGT's crept up = 20degs. That=20 confirmed, I was on the lean side ever since the restart.

Later = on, I=20 killed the carb heat, and while I could feel a TINY different in = vibration, it=20 was not significant.

Holy cow, it seems to run perfectly = happily on the=20 lean side, with an O-360! Who knew??

With that VERY informal = test out=20 of the way, I will now become well-versed with the lean finder mode on = the=20 engine monitor...today's flight was just to find out if I should = bother=20 digging deeper.  For a 60-80deg drop in CHT's, and 9.5gph instead = of=20 12gph (down low, least), I'll take it! 

I'm posting this = for=20 those that are interested in LOP, but haven't tried it with = non-injected power=20 plants.

Keith
N360JH
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