X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from yw-out-2324.google.com ([74.125.46.28] verified) by logan.com (CommuniGate Pro SMTP 5.2.4) with ESMTP id 2993492 for flyrotary@lancaironline.net; Fri, 27 Jun 2008 00:26:59 -0400 Received-SPF: pass receiver=logan.com; client-ip=74.125.46.28; envelope-from=wdleonard@gmail.com Received: by yw-out-2324.google.com with SMTP id 3so166807ywj.7 for ; Thu, 26 Jun 2008 21:26:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:in-reply-to:mime-version:content-type:references; bh=drmrN50/AQholB706FRa/PpJZ0Rq4IWlLxUawtVn3Ko=; b=cX8teGVUKsks+tUdpnEHDFxkjWrGA82N8DEVXIs9YS2ar/miaQZBlMFA75aOH3ABog U5amSF2FVMBpRLLlHZGt6QiE1z2vKPDwcGaYP7njLyXZLJe8BdgRN4goLBMVvkOWB8Z1 qTEBCVcGMePAsYegTebhnLh+GuVq0ZGe0DbtA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:in-reply-to:mime-version :content-type:references; b=AEHQLH8EoP623I4S95n606z8E2IVVCowm8hp3kaNZUqQdiOUt3wloeRUe7N8WIXLUl NpygxHfVSzNr3ET6EP02W9jKCQFnUtAEacuNIEFcx00jd3PSTVGcRT+GVAsemOFoUJfF gQ7aKTIvJ+NaEc31lQvWSHFH7OTLLVcq4c69U= Received: by 10.150.177.20 with SMTP id z20mr1408514ybe.214.1214540774195; Thu, 26 Jun 2008 21:26:14 -0700 (PDT) Received: by 10.150.145.16 with HTTP; Thu, 26 Jun 2008 21:26:14 -0700 (PDT) Message-ID: <1c23473f0806262126m69b991eak46d3c598d76797f2@mail.gmail.com> Date: Thu, 26 Jun 2008 21:26:14 -0700 From: "David Leonard" To: "Rotary motors in aircraft" Subject: Re: Running lean of peak In-Reply-To: <1c23473f0806262007k6eb072c9pf2e8606e47e4423a@mail.gmail.com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_6962_1804320.1214540774198" References: <1c23473f0806262007k6eb072c9pf2e8606e47e4423a@mail.gmail.com> ------=_Part_6962_1804320.1214540774198 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Hi Al, I would confirm your experience. It will continue to run 200 LOP, but even at 100 LOP it is starting to have significant misses. Even 50-60 LOP has = a much rougher feel than ROP, but the EGT's really start to fall off and fuel consumption drops. I have noticed that much of the problem is rotor balance. If one rotor is 20 ROP, the other may be well LOP. If I carefully work to match the rotors then I run much smoother well LOP. The problem for me is that my rotor balance is very dependent on RPM. If I get them matched at 5000 RPM, then they are WAY different at 6000 RPM and vise versa. (evidence of a very poor manifold design?!) For my next turbo destruction cycle, I plan to really focus on EGT (like cert engine pilots have to). I will balance the rotors at a particular RPM and only run LOP at that RPM. Otherwise, I will run ROP. If I can get the turbo to 500 hrs, that would be less than $2/hr and it would be worth it. Keep 2 turbos in cycle to the rebuild shop, and always the means to fly around n.a..... I'll let you know how it goes :-) Dave Leonard On Thu, Jun 26, 2008 at 7:25 PM, Al Gietzen wrote: > > > Al, > > How many hours are on your sparkplugs and are you useing auto fuel or > 100LL.........Something to > > consider before a 2000 mile trip.........Could be possible indication > before the dreaded "SAG".......... > > > > I don't recall (have to check the engine log), but I'd guess maybe 20 hrs= ; > only 10 ga 100LL; all the rest unleaded mogas. I took a leading and > trailing out yesterday to look at them and they look fine. > > > > Al > > > > -------------- Original message from "Al Gietzen" : > -------------- > > I'm finding that at about 100F LOP I sense that the engine is starting to > not like it =96 like it doesn't seem to be entirely smooth; maybe an > occasional miss here and there. Am I right that some of you guys run as > much as 200 LOP; or is it my imagination =96 in both cases. > > > > Would timing setting have much of anything to do with running LOP? > > > > Just past by the 100 hr mark on the engine near the end of a 500 mile tri= p > on Monday. I plan to leave next Monday on a round trip of over 2000 nm o= ver > the following week. That'll rack up a few hours. > > > > Al > > ------=_Part_6962_1804320.1214540774198 Content-Type: text/html; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline



Hi Al,

I would confirm yo= ur experience.  It will continue to run 200 LOP, but even at 100 LOP i= t is starting to have significant misses.  Even 50-60 LOP  has a = much rougher feel than ROP, but the EGT's really start to fall off and = fuel consumption drops.

I have noticed that much of the problem is rotor balance.  If one = rotor is 20 ROP, the other may be well LOP.  If I carefully work to ma= tch the rotors then I run much smoother well LOP.  The problem for me = is that my rotor balance is very dependent on RPM.  If I get them matc= hed at 5000 RPM, then they are WAY different at 6000 RPM and vise versa. (e= vidence of a very poor manifold design?!)

For my next turbo destruction cycle, I plan to really focus on EGT (lik= e cert engine pilots have to).  I will balance the rotors at a particu= lar RPM and only run LOP at that RPM.  Otherwise, I will run ROP. = ; If I can get the turbo to 500 hrs,  that would be less than $2/hr an= d it would be worth it.  Keep 2 turbos in cycle to the rebuild shop, a= nd always the means to fly around n.a.....  I'll let you know how = it goes  :-)

Dave Leonard


On Thu, Jun 26, 2008 at 7:25 PM, Al Gietzen <ALVentures@cox.net> wrote= :

=  

= Al,

=  How many hours are on your sparkplug= s and are you useing auto fuel or 100LL.........Something to

= consider before a 2000 mile trip.........C= ould be possible indication before the dreaded "SAG"..........

 

I don't recall (have to ch= eck the engine log), but I'd guess maybe 20 hrs; only 10 ga 100LL; all the rest unleaded mogas.  I took a leading and trailing out yesterday to look a= t them and they look fine.

 

Al

 

--= ------------ Original message from "Al Gietzen" <ALVentures@cox.net>: --------------

I'm finding that at abou= t 100F LOP I sense that the engine is starting to not like it =96 like it doesn't seem to be entirely smooth; maybe an occasional miss here and there.  Am I right that some of you guys run as much as 200 LOP; or is= it my imagination =96 in both cases.

=  

Would timing setting have mu= ch of anything to do with running LOP?

=  

Just past by the 100 hr mark= on the engine near the end of a 500 mile trip on Monday.  I plan to leave next Monday on a round trip of over 2000 nm over the following week.  That'll rack up a few hours.

=  

Al




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