X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 17 Aug 2011 09:29:08 -0400 Message-ID: X-Original-Return-Path: Received: from [198.64.152.110] (HELO sdc.com) by logan.com (CommuniGate Pro SMTP 5.4.1) with ESMTP id 5094922 for lml@lancaironline.net; Wed, 17 Aug 2011 08:28:03 -0400 Received-SPF: pass receiver=logan.com; client-ip=198.64.152.110; envelope-from=ronald@sdc.com Received: from [192.168.1.104] [68.202.60.124] by sdc.com with ESMTP (SMTPD-11.5) id a0b800023b1ce888; Wed, 17 Aug 2011 08:16:14 -0400 User-Agent: Microsoft-MacOutlook/14.2.0.101115 X-Original-Date: Wed, 17 Aug 2011 08:27:27 -0400 Subject: Re: [LML] How do I run lean of peak? From: RONALD STEVENS X-Original-To: Lancair Mailing List X-Original-Message-ID: Thread-Topic: [LML] How do I run lean of peak? In-Reply-To: Mime-version: 1.0 Content-type: multipart/alternative; boundary="B_3396414449_4319054" > This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --B_3396414449_4319054 Content-type: text/plain; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable Wow.=8Ado not only use the temps from your TIT and CHT to lean or in your cas= e to go richer. It really depends how good/bad your baffling is. If you like to be on the safe side than reduce MP to 26 (so you keep pressurization) then slowly pull and wait for the last EGT to peak, then lean further to go at least 75 degrees below that temp. Than you are LOP an= d can increase your MP back to 29 (some will run it up until 31.5 but I have had back firing at this manifold and also noticed that the speed increase was minimal, with 29 you are burning around 16.5 gph) Sure you can go hotter, but those few knots more is not worth stressing the engine. Now if you are getting used to this, then you can also keep the MP at 29 and just pull the mixture until you have a fuel flow of around 16.5 gph (which I do). Than keep an eye on the TIT (CHT will be usually very cool, in my case they are around 320@17500ft TIT +- 1600 or less) I discovered that going from 29 to 31.5 MAP the speeds increase are minimal but the fuel savings are nice. Just try it and see for yourself. Doesn't hurt as long as you are not running the engine at max EGT. In order to damage (detonation) your engine you need high pressures (max cruise), hot temps (CHT>420, TIT>1750) and a sick bag, because it will scar= e the crap out of you LOL Have fun flying =8B Ronald From: Dico Reijers Reply-To: Lancair Mailing List Date: Wed, 17 Aug 2011 07:43:23 -0400 To: Subject: [LML] How do I run lean of peak? Hi All, I am new to LOP operations and am looking for some help. I spoke with some IV-P owners in oshkosh about this and just wanted to get some more info and clarification. I understand that i should run ROP until altitude, then i can run LOP. The CHTs are supposed to be 390 or less and the TIT 1650 or less. So since i have not made the "big pull" before, i would like to know how exactly is th= e best way. Do i set the cruise power, say 30" and 2500rpm, then slowly turn out the mixture... Watch the temps rise ( how hot does it get before it starts to go down again?) and then keep leaning until i get the TIT back to 1650 and CHT to 380ish or below? How fast should the leaning happen? I understand i dont want to get the chts and tits really hot, so i presume i should be leaning relatively quickly (half a mixture turn per second?) Has someone ever made a little video with their point and shoot camera of this process while up in the air? This would be handy for someone new to running LOP. Thanks all, Dico --=20 Regards, Dico Reijers InternetWorks Ltd. 300 University Avenue Charlottetown PE, C1A 4M4 902-892-4671 (T) 888-368-9484 (F) www.internetworks.ca www.apartmentspei.com --B_3396414449_4319054 Content-type: text/html; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable
Wow.…do not only use t= he temps from your TIT and CHT to lean or in your case to go richer. It real= ly depends how good/bad your baffling is.

If you li= ke to be on the safe side than reduce MP to 26 (so you keep pressurization) = then slowly pull and wait for the last EGT to peak, then lean further to go = at least 75 degrees below that temp. Than you are LOP and can increase your = MP back to 29 (some will run it up until 31.5 but I have had back firing at = this manifold and also noticed that the speed increase was minimal, with 29 = you are burning around 16.5 gph)

Sure you can go ho= tter, but those few knots more is not worth stressing the engine. Now if you= are getting used to this, then you can also keep the MP at 29 and just pull= the mixture until you have a fuel flow of around 16.5 gph (which I do). Tha= n keep an eye on the TIT (CHT will be usually very cool, in my case they are= around 320@17500ft TIT +- 1600 or less) 

I di= scovered that going from 29 to 31.5 MAP the speeds increase are minimal but = the fuel savings are nice. Just try it and see for yourself. Doesn't hurt as= long as you are not running the engine at max EGT.

In order to damage (detonation) your engine you need high pressures (max cr= uise), hot temps (CHT>420, TIT>1750) and a sick bag, because it will s= care the crap out of you LOL

 Have fun flying = — Ronald 

From: <= /span> Dico Reijers <dico@internet= works.ca>
Reply-To: Lancair= Mailing List <lml@lancaironline.n= et>
Date: Wed, 17 Aug 2011 = 07:43:23 -0400
To: <lml@lancaironline.net>
Subject: [LML] How do I run lean of peak?
<= div>
Hi All,

I am new to LOP operations and am looking for s= ome help.  I spoke with some IV-P owners in oshkosh about this and just= wanted to get some more info and clarification.

I understand that i = should run ROP until altitude, then i can run LOP. The CHTs are supposed to = be 390 or less and the TIT 1650 or less. So since i have not made the "big p= ull" before, i would like to know how exactly is the best way.  Do i se= t the cruise power, say 30" and 2500rpm, then slowly turn out the mixture...= Watch the temps rise ( how hot does it get before it starts to go down agai= n?) and then keep leaning until i get the TIT back to 1650 and CHT to 380ish= or below?  How fast should the leaning happen? I understand i dont wan= t to get the chts and tits really hot, so i presume i should be leaning rela= tively quickly (half a mixture turn per second?)

Has someone ever mad= e a little video with their point and shoot camera of this process while up = in the air?  This would be handy for someone new to running LOP.
Thanks all,

Dico

--
Regards,

Dico Reijers

I= nternetWorks Ltd.
300 University Avenue
Charlottetown
PE, C1A 4M4
902-892-4671 (T)
888-368-9484 (F)

www.internetworks.ca
www.apartmentspei.com
 --B_3396414449_4319054--