X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Fri, 30 May 2008 19:05:47 -0400 Message-ID: X-Original-Return-Path: Received: from [66.64.141.200] (HELO lucky.dts.local) by logan.com (CommuniGate Pro SMTP 5.2.3) with ESMTP id 2945938 for lml@lancaironline.net; Fri, 30 May 2008 13:25:00 -0400 Received-SPF: none receiver=logan.com; client-ip=66.64.141.200; envelope-from=cjensen@dts9000.com Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C8C279.BD8D18D2" Subject: RE: [LML] Re: Electronic ignition spark plugs X-MimeOLE: Produced By Microsoft Exchange V6.5 X-Original-Date: Fri, 30 May 2008 13:22:30 -0400 X-Original-Message-ID: <8984A39879F2F5418251CBEEC9C689B3AFCDEA@lucky.dts.local> In-Reply-To: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [LML] Re: Electronic ignition spark plugs Thread-Index: AcjCWxM6F5+i1YxuQdmnIrbEfuZW5QAHhPdw From: "Chuck Jensen" X-Original-To: "Lancair Mailing List" This is a multi-part message in MIME format. ------_=_NextPart_001_01C8C279.BD8D18D2 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable George, =20 Your postings are quite surprising, and a bit disappointing. You point = out that auto plugs are different that aviation plugs. You point out = that you know the temperature of the aviation plugs during operations. = You point out that auto plugs enjoys a heat sunk environment. You point = out that the aviation plug was designed for the aviation environment. =20 All of these are true, but unfortunately, you leave us to 'conclude' = that that somehow means that the auto plug are unsatisfactory in the = aviation environment. I don't like having to bridge such gaps in data. = What is it about auto plugs that are inadequate? Peak temp tolerance? = Temp rate of change? Cylinder compression? 100LL gas? Where do they = fall short, other than they are 'different' from aviation plugs? =20 Personally, I run aviation plugs on both my mag and EI, but many have = run auto plugs without problems. Why, or how, were they successful when = there are so many implied deficiencies with auto plugs? Thanks,=20 Chuck Jensen=20 =20 -----Original Message----- From: Lancair Mailing List [mailto:lml@lancaironline.net]On Behalf Of = George Braly Sent: Friday, May 30, 2008 9:45 AM To: lml@lancaironline.net Subject: [LML] Re: Electronic ignition spark plugs Colyn, =20 Other than curiosity - - it is not, frankly, important that I know = what the number is supposed to be - -=20 =20 What is important is that nobody has a clue as to what the number is for = the automotive spark plug mounted in the aircraft application. =20 Keep in mind that the automotive spark plug enjoyes being "heat sunk" = into a massive water cooled cylinder head that is held at constant = temperature from a thermostat. =20 By contrast, the aircraft spark plug is desgined for the much more = variable environment of the air cooled cylinder head which can have = temperatures more than twice as high as the automotive cylinder head. =20 There is a casual acceptance of a substantial level of = "under-investigation" that is associated with some of these often = routinely accepted recommendations to use components that have not = undergone thoughtful testing at the boundary conditions of realistic = operating environments. =20 =20 Regards, George=20 =20 PS> The answer to your question is in some of the APS class materials. = We made a power point slide that detailed the aircraft spark plug = ceramic temperature as a function of A/F ratio. =20 _____ =20 From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of = Colyn Case at earthlink Sent: Wednesday, May 28, 2008 9:37 PM To: lml@lancaironline.net Subject: [LML] Re: Electronic ignition spark plugs George said I can tell you the answer to that question with respect to an aviation = spark plug. =20 okay, what's the answer? say, 50 dF LOP 32" TSIO-550 ....or whatever you = actually have. =20 =20 ------_=_NextPart_001_01C8C279.BD8D18D2 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
George,
 
Your=20 postings are quite surprising, and a bit disappointing.  You point = out that=20 auto plugs are different that aviation plugs.  You point out that = you know=20 the temperature of the aviation plugs during operations.  You point = out=20 that auto plugs enjoys a heat sunk environment.  You point out that = the=20 aviation plug was designed for the aviation = environment.
 
All of=20 these are true, but unfortunately, you leave us to 'conclude' that that = somehow=20 means that the auto plug are unsatisfactory in the aviation=20 environment.  I don't like having to bridge such gaps in = data. =20 What  is it about auto plugs that are inadequate?  Peak temp=20 tolerance?  Temp rate of change?  Cylinder compression?  = 100LL=20 gas?  Where do they fall short, other than they are 'different' = from=20 aviation plugs?
 
Personally, I run aviation plugs on both my mag and EI, but = many have run=20 auto plugs without problems.  Why, or how, were they successful = when there=20 are so many implied deficiencies with auto plugs?

Thanks, 
Chuck=20 Jensen

 

-----Original Message-----
From: Lancair Mailing = List=20 [mailto:lml@lancaironline.net]On Behalf Of George = Braly
Sent:=20 Friday, May 30, 2008 9:45 AM
To:=20 lml@lancaironline.net
Subject: [LML] Re: Electronic ignition = spark=20 plugs

Colyn,
 
Other than curiosity - -   it is = not,=20 frankly, important that I know what the number is supposed to be = - -=20
 
What is important is that nobody has = a clue=20 as to what the number is for the automotive spark plug = mounted in the=20 aircraft application.
 
Keep=20 in mind that the automotive spark plug enjoyes being "heat sunk"  = into a=20 massive water cooled cylinder head that is held at constant = temperature from a=20 thermostat.
 
By=20 contrast, the aircraft spark plug is desgined for the much more = variable=20 environment of the air cooled cylinder head which can have = temperatures more=20 than twice as high as the automotive cylinder = head.
 
There is a  casual acceptance of a = substantial=20 level of  "under-investigation"  that is = associated with=20 some of these often routinely accepted  recommendations to use = components=20 that have not undergone   thoughtful testing at the boundary = conditions of  realistic operating=20 environments.  
 
Regards,  George
 
PS>  The answer to your question is = in some=20 of the APS class materials.  We made a power point slide that = detailed=20 the aircraft spark plug ceramic temperature as a function of  A/F = ratio.
 

From: Lancair Mailing List=20 [mailto:lml@lancaironline.net] On Behalf Of Colyn Case at=20 earthlink
Sent: Wednesday, May 28, 2008 9:37 = PM
To:=20 lml@lancaironline.net
Subject: [LML] Re: Electronic ignition = spark=20 plugs

George said
I can tell you the answer to that question = with=20 respect to an aviation spark plug.
 
okay, what's the answer? say, 50 dF LOP 32" = TSIO-550=20 ....or whatever you actually have.
 
 
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