X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from ms-smtp-02.southeast.rr.com ([24.25.9.101] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with ESMTP id 1155828 for flyrotary@lancaironline.net; Thu, 15 Jun 2006 15:08:36 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.101; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-111-186.carolina.res.rr.com [24.74.111.186]) by ms-smtp-02.southeast.rr.com (8.13.6/8.13.6) with SMTP id k5FJ7aCD029845 for ; Thu, 15 Jun 2006 15:07:38 -0400 (EDT) Message-ID: <000301c690af$173edc70$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Remove Turbo Date: Thu, 15 Jun 2006 15:08:30 -0400 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=response Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 X-Virus-Scanned: Symantec AntiVirus Scan Engine ----- Original Message ----- From: "Ernest Christley" To: "Rotary motors in aircraft" Sent: Thursday, June 15, 2006 12:55 PM Subject: [FlyRotary] Re: Remove Turbo > Ed Anderson wrote: > >> Anything you can do to reduce the power and therefore heat your engine is >> developing will reduce the BTU of waste heat your cooling system must >> deal with. Leaning would reduce the heat load - but, whether >> sufficiently to materially affect your cooling is another story. My >> calculations shows the following: >> >> Rpm A/F ratio Fuel Flow BTU >> 1000 12:1 2.9 1417 >> 1000 14.7 2.3 1157 >> 1000 17.4 2.0 987 >> >> However, keep in mind that at lower idle RPM you need a richer mixture >> to keep the engine turning over, so you can not lean the engine as much >> at idle as you can up in the air at cruise. >> >> My 0.02 worth > > If it were possible, cutting the BTU by 30% would just have to help. > 'Course, that's just an semi-educated opinion. I was thinking a little > more throttle and a little less fuel, with the goal of having the excess > air carry off a disproportionate amount of heat. I've heard you say that > in cruise you can use the mixture knob to very effectively control power. > Why not on the ground? Set the throttle to quarter or even half open and > bring the mixture down till it will barely keep turning. > > Note: I still don't have an engine running, or I'd be experimenting with > this myself and reporting the results. > Be certain and let us know the results, Ernest. I suspect that you will find that the engine will want to pop and possibly spit back with the throttle open that much and the mixture lean, but I could certainly be wrong about that. Ed