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Guest Message by DevFuse

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Heresy! Replaced NGK Platinum w/Champion Copper Plugs

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32 replies to this topic

#26 friendly_jacek


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Posted 19 May 2004 - 08:46 AM

The crankshaft sensor fired coil pack type ignitions common on almost all new cars fire the two cylinders opposite each other in firing order at the same moment. One gets a spark when needed at roughly top dead center compression stroke, The other cylinder gets a spark that has no effect at roughly top dead center on the exhaust stroke.

Ya, it is a cost saving measure; but many cars have a separate coil per each plug...

#27 WRX Love

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Posted 21 May 2004 - 11:10 PM

legacy 2.5, modern vehicles do in fact require a plug of the correct heat range just as vehicles 30 years ago did, the difference is the addition of the "copper core" to spark plug technology who's contribution yields a broader effective heat-range by way of copper's thermal (sinking & releasing) properties. Essentially copper-core plugs are less prone to overheating on mountain grades and less prone to fouling around town.

I agree with your comment about the Champions, in fact it's almost universal that NGK's trump Champions, but why? I've finally dug-up some technical info that supports and explains what it is that everyone has been subjectively feeling:


All I want to say is than you VERY much for sharing that information (URL) with us.

#28 blitz



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Posted 22 May 2004 - 09:22 AM

Blitz: The article you cite, although interesting, doesn't mention Champions as "bad" plugs; it only mentions NGKs as "good" plugs. Therefore, it does not support your proposition that NGK plugs are superior to Champions (they may be, but the article doesn't say so or allow someone to conclude so).

Nothing said so far explains why two of the NGK platinum plugs I pulled after 44,500 mi appear severely worn or why the car's power and throttle response improved dramatically after replacing the NGK platinum plugs.

My argument is not that Champion is superior to NGK or vice versa, only that I suspect that platinum plugs don't last as long as claimed and that if changed frequently inexpensive copper plugs may outperform overpriced platinum plugs.

Did we read the same article? :)

Here's my summation:

The authors spark-plug "quest" began as a result of a misfire in a new Neon (Champions). His findings were that the added resistance in many resistor type plugs (including the factory-installed plugs in his Neon) is deemed too high for good ignition and tended to cause misfires under certain conditions. He then measured the resistance of all the popular plugs and found NGK to be the lowest.

Agreeably, there are other things that can affect spark plug performance like electrode dimensions, electrode material, and manufacturing defects as a result of crappy QC, but the article doesn't dwell on those issues.

#29 swami2806


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Posted 23 May 2004 - 08:07 AM

Wow! Lookes like my knowledge of ignitions are a bit dated! Ya learn something new every day.

#30 Tiny Clark

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Posted 24 May 2004 - 12:39 AM

Reverse Polarity Spark? Toto, I don't think we're in Kansas anymore...

I really have a hard time swallowing this one, as a matter of fact I can't even force myself to sniff at the bait!

Until they come up with a camera that can stop action the spark right in the middle of it's path, I'm not buying it.

#31 avk


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Posted 24 May 2004 - 08:10 AM

You already bought it, with the car! "Reverse" and "direct" are relative terms, anyway.

#32 blitz



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Posted 24 May 2004 - 10:41 AM

Reverse Polarity Spark? Toto, I don't think we're in Kansas anymore...

I really have a hard time swallowing this one, as a matter of fact I can't even force myself to sniff at the bait!

Until they come up with a camera that can stop action the spark right in the middle of it's path, I'm not buying it.

Tiny, Shadow explains it best. The front coil is firing the front two plugs (left side & right side) simultaneously in a SERIES circuit, which would make the polarity of left plug opposite that of the right plug. This means that the coil must develop enough voltage to ionize two .040 gaps in series (essentially .080 worth of gap) as well as overcome the resistance of both plugs (and wires) in series all at the same time.

But why series? Balance. If the pair of plugs were connected in parallel off of the coil secondary, one plug would always ionize and spark first, depriving the other of spark. In series, both plugs receive equally the full current developed by the coil after inonization is achieved.

Electrons move from negative to positive (from cathode to anode) and will transfer a small amount of metal in the same direction (from the cathode to the anode), so on one side of the engine, the metal is being transferred OFF OF the center electrode (cathode) and on the other side it's being transferred ONTO the center electrode (anode).

Not sure if I made things more confusing. :-\

#33 Tiny Clark

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Posted 25 May 2004 - 02:16 AM

avk, I bought into it only as an innocent bystander.

Blitz (and all others), OK, OK, I understand all this theory mumbo jumbo (unfortunately, I make a living at trying to fix crap that engineers dream up) about the series circuit and anodes and cathodes, and lions and tigers and bears, Oh My!

Me thinks it would work in parallel as well due to decreased resistance of the plug gap on the combustion stroke, but I have to bow out to the pocket protector & RPG/BCG wearing geeks on this one.

But remember, these are the same guys that put the parking light switch on the steering column and the drink holder in the perfect spot next to the climate controls and above the radio, supported slightly enough to bounce around a can of Coke so that it will completely disperse its carbonation in a few short minutes.

Better break the microscope out to see the deposits tho, at least on mine. I just changed my regular old AC copper plugs out after almost 30,000 miles and didn't see any NOTICEABLE difference in them. Anyway, and theoretically of course, if the deposits go from one side to the other, then the build-up and tear-down should result in the gap staying the same. :brow:

However, the extra acceleration and power I didn't feel with the new "platinum quad-spark dilithium crystal super high output beryllium coated superconductor center core plugs" I installed really put the hurt my neck during the test drive, and my gas mileage went from about 25.220 mpg to 25.255 mpg...

Satirically yours, Tiny

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