X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 30 [X] Return-Path: Received: from mail.fdic.gov ([167.176.6.5] verified) by logan.com (CommuniGate Pro SMTP 5.1.3) with ESMTPS id 1639665 for flyrotary@lancaironline.net; Mon, 04 Dec 2006 14:57:56 -0500 Received-SPF: pass receiver=logan.com; client-ip=167.176.6.5; envelope-from=brogers@fdic.gov DKIM-Signature: a=rsa-sha1; d=fdic.gov; s=fdic; c=simple; q=dns; t=1165262251; x=1165348651; h=from:date:subject:message-id:content-class:content-type; b=LMjTaoUTqeFxVw1qG4JWnDl8VyQILEgMrBJIH02NZpiaoyeXdj0YPRtA8XgVJkU3KMnTo3dtwGiTUh4s4XkBJQ== X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C717DE.62FB0D32" Subject: RE: [FlyRotary] Re: Spark Plug Fouling and Temperature Date: Mon, 4 Dec 2006 13:57:10 -0600 Message-ID: <15839C662A43B844B6E393DBFEAA90BF0570E225@dalexc101p.prod.fdic.gov> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [FlyRotary] Re: Spark Plug Fouling and Temperature Thread-Index: AccOoorhsG33MNzzTme/TOTYN3dMkQJONCRA From: "Rogers, Bob J." To: "Rotary motors in aircraft" Return-Path: BRogers@FDIC.gov X-OriginalArrivalTime: 04 Dec 2006 19:57:12.0199 (UTC) FILETIME=[6372B970:01C717DE] This is a multi-part message in MIME format. ------_=_NextPart_001_01C717DE.62FB0D32 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable If we are using Tracy's Fuel/Ignition Controller (which fires both Leading and Trailing Plugs at the same time), why is it necessary to have two different heat ranges of plugs? =20 =20 The stock Mazda 13B engine from 1986 to 1992 calls for NGK BUR7EQ in the leading plug and BUR9EQ in the trailing plug. I assume that the different heat range is because the stock engine has the two plugs firing at a different time. It is understandable that if the trailing plug fires later, then the mixture has already heated up and that plug needs to be colder. However, if both plugs fire at the same time, it seems to me that they should both be of the same heat range, whatever one you eventually decide on. =20 I have found that my trailing plugs (NGK BUR9EQ) foul quickly at low RPMs (idle up to 3,000), while the leading plugs (NGK BUR7EQ) do not. Since I am using Tracy's controller, I am thinking of running the hotter plug (BUR7EQ) in both leading and trailing positions. Or maybe I should compromise and run BUR8EQ all around. =20 Does anyone have experience with the platinum version of these plugs (BUR*EQP)? =20 =20 ________________________________ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ed Anderson Sent: Wednesday, November 22, 2006 7:50 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Spark Plug Fouling and Temperature =20 Its interesting, we I use 100LL I usually get 25 hours on a set of plugs. I wonder what factors might make the difference between your time interval and mine - "Plugs Up"?. I have not run across any chart that indicated anything other than a plug digit which indicated a "hotter" or a "colder version". I think I may try hotter plugs and see if they make any difference. =20 Ed=20 ----- Original Message -----=20 From: Perry Mick =20 To: Rotary motors in aircraft =20 Sent: Wednesday, November 22, 2006 8:26 PM Subject: [FlyRotary] Spark Plug Fouling and Temperature =20 Ed, thanks for that article. I installed the hotter plugs, BUR6EQ leading and BUR8EQ trailing a month or so ago. I guess I'll have to start burning 100LL to see if it fixes the fouling problem. I usually only burn it when I'm travelling and have no other choice, but don't have any trips planned soon. For me, it only takes 4 hours of continuous 100LL use to get SAG and fouled leading plugs on the next takeoff. Is there any data anywhere that might tell us what temperature BUR6EQ, 7EQ, 8EQ, and 9EQ plugs operate at in an RX-7? =09 Perry http://www.ductedfan.com =20 ----- =09 =09 ------_=_NextPart_001_01C717DE.62FB0D32 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

If we are using Tracy’s Fuel/Ignition = Controller (which fires both Leading and Trailing Plugs at the same time), why is = it necessary to have two different heat ranges of plugs?   =

 

The stock Mazda 13B engine from = 1986 to 1992 calls for NGK BUR7EQ in the leading plug and BUR9EQ in the trailing plug.  I assume that the = different heat range is because the stock engine has the two plugs firing at a = different time.  It is understandable = that if the trailing plug fires later, then the mixture has already heated up = and that plug needs to be colder.  = However, if both plugs fire at the same time, it seems to me that they should both = be of the same heat range, whatever one you eventually decide = on.

 

I have found that my trailing plugs = (NGK BUR9EQ) foul quickly at low RPMs (idle up to 3,000), while the leading plugs = (NGK BUR7EQ) do not.  Since I am = using Tracy’s = controller, I am thinking of running the hotter plug (BUR7EQ) in both leading and = trailing positions.  Or maybe I = should compromise and run BUR8EQ all around.

 

Does anyone have experience with = the platinum version of these plugs (BUR*EQP)?  

 

From: Rotary motors in = aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ed Anderson
Sent: Wednesday, November = 22, 2006 7:50 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: = Spark Plug Fouling and Temperature

 

Its interesting, we I use 100LL I usually get = 25 hours on a set of plugs.  I wonder what factors might make the = difference between your time interval and mine - "Plugs = Up"?.  I have not run across any chart that indicated anything other than a plug digit = which indicated a "hotter" or a "colder version".  I = think I may try  hotter plugs and see if they make any = difference.

 

Ed 

----- Original Message ----- =

From: Perry = Mick

Sent: Wednesday, November 22, 2006 8:26 PM

Subject: [FlyRotary] Spark Plug Fouling and Temperature

 

Ed, thanks for that article.
I installed the hotter plugs, BUR6EQ leading and BUR8EQ trailing a month = or so ago.
I guess I'll have to start burning 100LL to see if it fixes the fouling problem.
I usually only burn it when I'm travelling and have no other choice, but = don't have any trips planned soon.
For me, it only takes 4 hours of continuous 100LL use to get SAG and = fouled leading plugs on the next takeoff.
Is there any data anywhere that might tell us what temperature BUR6EQ, = 7EQ, 8EQ, and 9EQ plugs operate at in an RX-7?

Perry
http://www.ductedfan.com
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