From autox-owner@triumph.cs.utah.edu Wed Apr 19 13:58 PDT 1995 Received: from mailer by fshpp1 with SMTP (1.38.193.4/16.2) id AA14604; Wed, 19 Apr 1995 13:58:11 -0700 Return-Path: Received: from triumph.cs.utah.edu by UG.EDS.COM (PMDF V4.3-10 #4) id <01HPIXEQ3P8G000XMC@UG.EDS.COM>; Wed, 19 Apr 1995 13:55:38 -0700 (PDT) Received: (from majordom@localhost) by triumph.cs.utah.edu (8.6.10/8.6.6) id PAA07647 for autox-outgoing; Wed, 19 Apr 1995 15:50:10 -0400 Date: Wed, 19 Apr 1995 13:44:20 -0600 (MDT) From: fmicos!shogun!gmorrell@uunet.uu.net (Gary Morrell) Subject: Re: Splitfires Sender: owner-autox@triumph.cs.utah.edu To: uunet!autox.team.net!autox@uunet.uu.net Reply-To: fmicos!shogun!gmorrell@uunet.uu.net (Gary Morrell) Message-Id: <9504191944.AA14350@shogun.COS.eld.ford.com> X-Envelope-To: JAN@FSHPP1 Content-Transfer-Encoding: 7BIT Precedence: bulk Status: RO / Andy Hollis relates a tale of sparkplugs, endly thusly: / > Well, when I pulled off the plugs from the van (stock OEM), the plugs were / > DIFFERENT from one side of the V6 to the other. One side had the same as / > the Autolites (and my old Aerostar) with a single nub on the center / > electrode. The other side had only a single nub on the ground electrode. / > Kinda like the top half of the Autolite "double platinum". Very bizarre, / > indeed. / Some newer engines have two plugs connected to a single coil, and always / spark together, (my Miata is one, and the GM Quad IV is another). One / of the two plugs is wired in backwards, so that the spark jumps in the / opposite direction from normal. / Now, I have heard that the platinum is only required on one electrode. / (And it is not recommended to put the platinum plugs in a Miata, as / two of them will not take advantage of that platinum.) / If your Aerostar is configured like this, then having two sparkplugs / with the platinum on the opposite electrode would help. Perhaps / those Ford engineers actually knew what they were doing. / I would check it out, and put in the same type of plug that you / originally found in there. / Tom Tkacik Tom is on the right track. On many modern engines with distributorless ignition systems, each pair of spark plugs is connected in series to a single high voltage coil. e.g. A 6 cylinder engine would have 3 high voltage coils, each series connected to a pair of plugs. By series connected, I mean that one plug is connected to _each_ end of the high voltage coil, neither side of the coil is connected directly to ground. This causes one plug to fire with a positive polarity with respect to the outer grounded electrode and the other plug to fire negative wrt ground. Spark plugs will always tend to erode (sacrifice) their negative electrodes faster than their positive electrodes, therefore, in a series connected distributorless ignition, the positive plug will erode its outer electrode and the negative plug will erode its center electrode. Platinum plating (or nubs as Andy calls 'em) helps the plugs electrodes resist erosion. Ford was simply trying to save Platinum and $ by supplying plugs that had selective plati I haven't seen an Aerostar manual lately, I would suspect that the listed replacement plug is something like a Motorcraft AGSP32PP, PP meaning that both electrodes have Platinum nubs. This means that the consumer can replace all the plugs without worrying if the right plug is going into the correct cylinder. The main reason that the auto manufacturer's are going to Pt plugs is to meet new EPA and CARB emissions performance-vs-miles requirements. New regulations for the TLEV and ULEV (Transitional Low Emissions Vehicle, Ultra Low Emissions Vehicle) cars require that emissions remain in spec for 50,000+ miles. Pt plugs is just one of the techniques used to achieve this. Gary Morrell Senior Test Engineer Ford Motor Company Colorado Springs, CO _______________________________________________________________________________ Opinions expressed are the author's and may not reflect those of Ford Motor Company or its subsidiaries. _______________________________________________________________________________ From autox-owner@triumph.cs.utah.edu Wed Apr 19 09:37 PDT 1995 Received: from mailer by fshpp1 with SMTP (1.38.193.4/16.2) id AA21385; Wed, 19 Apr 1995 09:37:10 -0700 Return-Path: Received: from triumph.cs.utah.edu by UG.EDS.COM (PMDF V4.3-10 #4) id <01HPIOAZA4GW000P5B@UG.EDS.COM>; Wed, 19 Apr 1995 09:34:32 -0700 (PDT) Received: (from majordom@localhost) by triumph.cs.utah.edu (8.6.10/8.6.6) id LAA04453 for autox-outgoing; Wed, 19 Apr 1995 11:42:29 -0400 Date: Wed, 19 Apr 1995 09:21:50 -0600 (MDT) From: fmicos!shogun!gmorrell@uunet.uu.net (Gary Morrell) Subject: Re: Splitfires Sender: owner-autox@triumph.cs.utah.edu To: uunet!autox.team.net!autox@uunet.uu.net Reply-To: fmicos!shogun!gmorrell@uunet.uu.net (Gary Morrell) Message-Id: <9504191521.AA14165@shogun.COS.eld.ford.com> X-Envelope-To: JAN@FSHPP1 Content-Transfer-Encoding: 7BIT Precedence: bulk Status: RO On the Taurus SHO list we just got finished with the Split Fire thread. Allow me to post a part of the message that I put to that list: ...Soapbox On... (I'm gonna piss off a few people right here...) Being an engineer for an automotive company, I am frequently asked questions like: "Should I put Split-fire plugs in my car, should I use Slick 50, should I put that Power-Up magnet thingee on the fuel line (you know, that thing that lines up the fuel molecules?, geeze...), etc?" My stock response is this: If any of these aftermarket products actually yielded the performance and/or fuel economy gains that their manufacturer's claimed, don't you think that we, the automotive manufacturers, would be screwing this stuff into cars on the assembly line? We are constantly under the CAFE and EPA microscope to improve emissions and fuel economy. Hell, if Split-fire plugs would give us just a 1 or 2% fleetwide improvement in MPG and reduce emissions to boot, they (Split-Fires) would be in every car we build. BTW, fleetwide is 10 million cars a year for Ford, so +2% improvement in CAFE would save Ford millions of $ in non-attainment fines. The facts are that when these products are subjected to real world, controlled testing, their benefits are sometimes marginal, occasionally negative, and most often, lost in the noise. These products are sold on testimonials, not test data. The only people who benefit from these products are the guys collecting the profits from your purchase. ...Soapbox Off... Gary Morrell Senior Test Engineer Ford Motor Company Colorado Springs, CO (719) 528-7912 _______________________________________________________________________________ Opinions expressed are the author's and may not reflect those of Ford Motor Company or its subsidiaries. _______________________________________________________________________________