X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 30 May 2007 19:27:51 -0400 Message-ID: X-Original-Return-Path: Received: from ironport5.liveoakmail.com ([216.110.12.21] verified) by logan.com (CommuniGate Pro SMTP 5.1.9) with ESMTP id 2075629 for lml@lancaironline.net; Wed, 30 May 2007 19:23:18 -0400 Received-SPF: none receiver=logan.com; client-ip=216.110.12.21; envelope-from=walter@advancedpilot.com X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AgAAADOkXUZAMf4VeWdsb2JhbACCLzSNGwEBCQ4s X-IronPort-AV: E=Sophos;i="4.14,595,1170655200"; d="scan'208,217";a="15597489" Received: from rs5.liveoakhosting.com (HELO secure5.liveoakhosting.com) ([64.49.254.21]) by ironport5.liveoakmail.com with ESMTP; 30 May 2007 18:22:40 -0500 Received: (qmail 28875 invoked from network); 30 May 2007 18:22:40 -0500 Received: from 216-107-97-170.wan.networktel.net (HELO ?10.0.1.3?) (216.107.97.170) by rs5.liveoakhosting.com with (AES128-SHA encrypted) SMTP; 30 May 2007 18:22:40 -0500 Mime-Version: 1.0 (Apple Message framework v752.3) In-Reply-To: References: Content-Type: multipart/alternative; boundary=Apple-Mail-1-396661684 X-Original-Message-Id: <92288A6E-A74E-4CC6-ACBC-FEE8DCE06323@advancedpilot.com> From: Walter Atkinson Subject: Re: [LML] Re: TSIO 550 LOP X-Original-Date: Wed, 30 May 2007 18:22:04 -0500 X-Original-To: "Lancair Mailing List" X-Mailer: Apple Mail (2.752.3) --Apple-Mail-1-396661684 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed I've run two engines to TBO running at 87% power, about 80dF LOP. We know of several hundred others... The ICPs are low and the top end does not suffer. This is less stress on the cylinders than 75% power ROP! Walter On May 30, 2007, at 6:17 PM, Jack Cowell wrote: How far LOP are you at those numbers, Bob and on what is that LOP # based -- TIT, first cylinder to peak or ...? Also, what do you calculate your power percentage is at the numbers you provided? My TCM "guru" says stay at or below 70% power if you want the top end to live . On 5/30/07, Lancair wrote: Following this thread I have read a lot about pilots flying behind a TSIO550 and burning 17.5 gph. My ES-P (7.5 CR) flys at FL250 set at 31.5" and 2500 rpm, burning 15.5-16.0 gph LoP and showing a TAS of 230 +kt. I have a LightSpeed dual EI system and turn an MT 4-blade prop. Robert M. Simon ES-P N301ES From: PTACKABURY@aol.com [mailto: PTACKABURY@aol.com] Sent: Tuesday, May 29, 2007 11:00 PM To: lml@lancaironline.net Subject: Re: [LML] Re: TSIO 550 LOP In a message dated 5/29/2007 11:10:10 A.M. Pacific Daylight Time, walter@advancedpilot.com writes: OK, Paul, let's review the issue. Compression ratio: The higher CR WILL ALWAYS result in a lower EGT/TIT if all else is held constant. Why? Boyle's Law. PV = nRT. As the volume expands, the gas temperature goes down. More expansion; more temp loss = lower EGT. Walter: There is no issue here to review, so please step away from the tutorial podium. I fat fingered my previous email and met 17.5 rather than 7.5 so I was intending to compare a rate to a rate. Your simplistic physics above is all just dandy, but all else is never held constant. The timing recommended by the engine builder for a 8.5 and 7.5 are different, the MP is different to recapture some of the detonation margin and so on. All this has little to do with my original question which was at the same rate of consumption of a precious resource, disposable income, what sort of KIAS are LIV drivers achieving. You said in a previous email that a typical cruise fuel flow LOP for the TSIO-550 is 17.5 gph so fine, what indicated airspeeds are we seeing and if anyone now cares, if there are differences what accounts for those differences. If higher CRs are more fuel efficient as has been stated by many, well I would expect to see LIVs equip with those engines cruising at 17.5gph attaining a higher indicated airspeed. I chose KIAS because I thought it would simplify data collection. Simple stuff, and since I did not spend my time building a test stand, meaningful stuff at least for me. paul See what's free at AOL.com. --Apple-Mail-1-396661684 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=ISO-8859-1 I've run two engines to TBO = running at 87% power, about 80dF LOP.=A0 We know of several hundred = others...=A0 The ICPs are low and the top end does not suffer.=A0 This = is less stress on the cylinders than 75% power ROP!

Walter


On May 30, = 2007, at 6:17 PM, Jack Cowell wrote:

How far LOP are you at = those numbers, Bob and on what=A0is that LOP # based -- TIT, first = cylinder to peak or ...? Also, what do you calculate your power = percentage is at the numbers you provided? My TCM "guru" says stay at or = below 70% power if you want the top end to live
.
On 5/30/07, Lancair <lancair-esp@ustek.com> = wrote:
Following this thread I have read a lot = about pilots flying behind a TSIO550=A0and burning 17.5 gph.=A0 My ES-P = (7.5 CR)=A0flys at FL250=A0set at=A031.5" and 2500 rpm, burning = 15.5-16.0 gph LoP=A0and showing a TAS of 230+kt.=A0 I have a LightSpeed = dual EI system and turn an MT 4-blade prop.
=A0
Robert M. Simon
ES-P N301ES
=A0

From: PTACKABURY@aol.com [mailto: PTACKABURY@aol.com]
Sent: Tuesday, May = 29, 2007 11:00 PM
To: lml@lancaironline.net
Subject: Re: = [LML] Re: TSIO 550 LOP

=A0
In a message dated 5/29/2007 11:10:10 A.M. Pacific = Daylight Time, walter@advancedpilot.com writes:
=
OK, Paul, let's review the issue.=A0=A0

=A0
=
Compression ratio:
The higher CR WILL ALWAYS result in a = lower EGT/TIT if all else is held constant.=A0 Why?=A0 Boyle's Law.=A0 = PV =3D nRT.=A0 As the volume expands, the gas temperature goes down.=A0 = More expansion; more temp loss =3D lower EGT. =
Walter:
=
There is no issue here to review, so please step away from the = tutorial podium.=A0 I=A0fat fingered=A0my previous email and met 17.5 = rather than 7.5 so I was intending to compare a rate to a rate.=A0 Your = simplistic physics above=A0is all just dandy, but all else is never = held constant.=A0 The timing recommended by the engine builder for a = 8.5 and 7.5 are different, the MP is different to recapture some of the = detonation margin and so on.=A0 All this has little to do with my = original question which was at the same rate of consumption of a = precious resource, disposable income, what sort of KIAS are LIV drivers = achieving.=A0 You said in a previous email that a typical cruise fuel = flow LOP for the TSIO-550 is 17.5 gph so fine, what indicated airspeeds = are we seeing and if anyone now cares, if there are differences what = accounts for those differences.=A0 If higher CRs are more fuel efficient = as has been stated by many, well I would expect to see LIVs equip with = those engines cruising at 17.5gph attaining a higher indicated = airspeed.=A0 I chose KIAS because I thought it would simplify data = collection.=A0 Simple stuff, and since I did not spend my time building = a test stand, meaningful stuff at least for me.
=
paul



See what's = free at AOL.com. =


= --Apple-Mail-1-396661684--