Why do people use cheap copper plugs still?

[edhackett]

I hate to burst all you platinum/iridium users bubble, but those are copper plugs too. The Copper is used in the core of them and "copper" plugs for heat transfer. See the data posted earlier. "Copper plugs have steel or a nickel alloy electrodes, not copper. A spark will initiate from an iron-nickel alloy easier than it will across platinum or iridium. This can be noticeable in lower voltage ignitions and/or the specific characteristics of the ignition system.

Ed

 

[mechtech2]

Originally Posted By: earlyre
Originally Posted By: beast3300
Cheap Autolite coppers are the choice of the 3800 community. (or copper NGK as a second favorite).

Really why wouldn't you use copper spark plugs? They aren't hard to change. Generally 20-30k replacement for a nice refresh.


Originally Posted By: GatorJoe
Copper Champion spark plugs (RC12YCC OEM) are still a great choice for X300 Jaguars (1995-1997) based on what I've read. They seem to work well with the on-plug ignition coils.


the Champion RC9YC Coppers are the OE plug for my '05 Neon.
and i remember reading a thread over @ Dodgeforum.com, where something about the waste-spark ignition (which the neon has)doesn't play well with platinum plugs unless it's a double platinum (platinum on BOTH electrodes.)
(and anyone PLEASE feel free to correct me if i'm talking bollocks)


Many factory waste spark ignition cars had only one platinum tip. It would vary by what cylinder it was in, whether it was on the center or 'ground' electrode. Replacement plugs are almost always double plats. They just were saving money with the single plats.

And since we can get copper precious metal tipped plugs, why do people always treat the term 'copper plug' in a singular faceted state?

 

[mechtech2]

Originally Posted By: dparm
Copper doesn't last. Here are the melting points of some commonly used metals (Celsius):

Zinc == 420
Aluminum == 660
Copper == 1083
Steel == 1400-1500
Platinum == 1772
Iridium == 2410



Here are the thermal conductivities of some commonly used metals (Watts / centimeter*Kelvin):


Zinc == 1.16
Aluminum == 2.37
Copper == 4.01
Steel == 0.70 - 0.82
Platinum == 0.716
Iridium == 1.47


As you can see, copper is pretty much unbeatable for thermal conductivity.


Yes, but who cares how a heat range is achieved??
The copper plug can be cooler or hotter , or a non copper plug can be cooler or hotter.
You are right about not using zinc spark plugs!

 

[Kestas]

Originally Posted By: dparm
Copper doesn't last. Here are the melting points of some commonly used metals (Celsius)....

I don't understand your comment about "copper doesn't last", then you cite the melting points of different metals. Are you saying there is a problem with copper melting in the spark plug? I've never heard of or seen a documented case.

 

[SteveSRT8]

Originally Posted By: edhackett
I hate to burst all you platinum/iridium users bubble, but those are copper plugs too. The Copper is used in the core of them and "copper" plugs for heat transfer. See the data posted earlier. "Copper plugs have steel or a nickel alloy electrodes, not copper. A spark will initiate from an iron-nickel alloy easier than it will across platinum or iridium. This can be noticeable in lower voltage ignitions and/or the specific characteristics of the ignition system.Ed


Ed, that is common knowledge here, at least for most.

And it is totally wrong to imagine that a fine wire iridium electrode takes more voltage to fire than a nickel one!!!

Might want to give that one a think session....

 

[bdcardinal]

I use the OEM plugs for the cars I work on. On the R car, the aftermarket plugs just are not right for the longer reach on the R cars. They don't differentiate between a T5 and the R motor for some reason. The Volvo plugs get changed every 30K per the manual and they are only around $35 for the 5 pack from the dealer.

 

[edhackett]

True, Steve. The finer wire does mitigate the firing voltage differences. When it comes to lighting the fire, especially in a high performance engine, NGK says their "plain" electrode V-Power is the best. That's more due to spark geometry than electrode material. Platinum and Iridium are great for durability, but when it comes to performance, a "copper" plug can still be the best.

Ed

 

[Jarlaxle]

Originally Posted By: jeepman3071
Originally Posted By: VNTS
because a lot of engines cam factory with copper plugs.
copper is the best conductor. Some engines will trigger cell codes and run like [censored] with platinum and iridium.

lastly I would rather swap plugs every 30 K knowing they wont be seized in the head versus rolling the dice I can get them out at 100K.

BTW in all my 4 cylinders I can swap the plugs in about a 1/2 hr max.

Originally Posted By: hattaresguy
I'm surprised people are still using them. I don't like to make work, so I really like those super duty modern Iridium plugs than can got 100k or 200k miles in some cases.

Why do something several times over the life of the engine, when it can only be done once or twice?

OTOH copper plugs are great in pre 90 German cars.



This. My Jeep 4.0 will misfire and make the dash light up like a christmas tree on anything but copper plugs. The more electrodes the plugs have the less cylinders it will run on.

Mine is running fine on Bosch Platinums...but only because when I did the plugs, nobody could actually get me six copper-cores that weren't from China! (I removed badly-worn Delcos.)

 

[The_Eric]

Originally Posted By: Astro14
I put Bosch Platinum plugs in my '85 Volvo 240 (intercooled turbo, K-Jetronic) and it ran worse than it had with worn copper plugs. replaced cap & rotor at the same time. Figured I must have damaged a wire while changing plugs, so replaced the wires. Still ran worse, not awful, but noticeably worse.

Changed back to copper core plugs and lo and behold, it ran better than on the Platinums.

Can't explain it, but that B21FT (Red Block for the Volvo nuts) liked copper better...

See below.

Originally Posted By: edhackett
I hate to burst all you platinum/iridium users bubble, but those are copper plugs too. The Copper is used in the core of them and "copper" plugs for heat transfer. See the data posted earlier. "Copper plugs have steel or a nickel alloy electrodes, not copper. A spark will initiate from an iron-nickel alloy easier than it will across platinum or iridium. This can be noticeable in lower voltage ignitions and/or the specific characteristics of the ignition system.

Ed

The plug will still, for the most part fire just fine. It just takes more work from the coil to jump the same gap on a typical platinum plug vs. a conventional copper core plug. How noticeable it will be can vary.

I feel that this is evidenced in the above quotes; Astro dropped some platinum plugs in a system that didn't have the firepower that today's modern systems do and experienced issues. I think that most modern ignition systems will fire most anything thrown their way, as I've pulled countless dozens of .080" to .100"+ (my gap gauge only measures to around .100") and many still ran okay - some with no perceivable improvement.

 

[Astro14]

I think that in the case of my '85 Volvo - it was more a question of spark needed under boost. Coil was good, and while the system didn't create the voltage of a modern system, it was a good, strong spark.

Even then, it needed all the help it could get when under 10.5 PSI of boost...I've had other, older vehicles that ran great with platinum plugs, as long as they were gapped correctly.

Now, if someone made platinum plugs for the Packard, I would give them a try...but for a flat head 8, the only options I've seen are regular copper plugs...and that 6 volt coil needs all the help it can get...

 

[LeakySeals]

Originally Posted By: The_Eric
Originally Posted By: Astro14
I put Bosch Platinum plugs in my '85 Volvo 240 (intercooled turbo, K-Jetronic) and it ran worse than it had with worn copper plugs. replaced cap & rotor at the same time. Figured I must have damaged a wire while changing plugs, so replaced the wires. Still ran worse, not awful, but noticeably worse.

Changed back to copper core plugs and lo and behold, it ran better than on the Platinums.

Can't explain it, but that B21FT (Red Block for the Volvo nuts) liked copper better...


See below.



Originally Posted By: edhackett
I hate to burst all you platinum/iridium users bubble, but those are copper plugs too. The Copper is used in the core of them and "copper" plugs for heat transfer. See the data posted earlier. "Copper plugs have steel or a nickel alloy electrodes, not copper. A spark will initiate from an iron-nickel alloy easier than it will across platinum or iridium. This can be noticeable in lower voltage ignitions and/or the specific characteristics of the ignition system.



Ed







The plug will still, for the most part fire just fine. It just takes more work from the coil to jump the same gap on a typical platinum plug vs. a conventional copper core plug. How noticeable it will be can vary.

I feel that this is evidenced in the above quotes; Astro dropped some platinum plugs in a system that didn't have the firepower that today's modern systems do and experienced issues. I think that most modern ignition systems will fire most anything thrown their way, as I've pulled countless dozens of .080" to .100"+ (my gap gauge only measures to around .100") and many still ran okay - some with no perceivable improvement.

My understanding is its all about the efficiency of the small iridium tip. It requires less voltage to make a spark, which makes it less taxing to the coils in a modern coil over setup. Replacing a coil is not cheap. The other is the efficiency of the spark and its relationship to combusting most of the fuel in the combustion chamber. Thats good for a lot of reasons including the health of my cat. Thats what I have been told at the dealer when I asked about cheaping out on coppers. That I could get away with it, but there are potential consequences.

 

[virginoil]

Interesting reading feedback regarding the platinum and iridium on certain performance sites.

Most tuners seem to say use the copper for performance, the main reasons seems to be inability of the small diameter electrode to remain in place due to the high combustion temperature.

ZZperformance on their site indicate that the iridium plug provides the best performance despite the cost providing the correct plug is selected for stock or slightly modified vehicles.

Sparkplugs.com did a test of copper v platinum v iridium and they found the iridium plug gave the best overall consistency of spark with a very slight increase in power and torque. The test results are on heir website.

The iridium plug seems the way of the future.

For me the key aspects is to select the plug that provides the best spark to reduce the risk of misfire occurring, best for emissions and self cleaning and elimination of pre-ignition.

It is noted that little power and torque is usually gained from spark plugs.

When I ran the ACDelco Rapidfire thin electrode plug seemed to have improved the idle and it smoothed out the acceleration and the ever so slight hesitation in the change of gears.

I have posted a thread where I have come to believe that you can use a spark plug 1 heat range hotter for the iridium ones compared to the standard copper plug for the vehicle in question as the iridium’s :
• handle the heat better and
• ensures maximum efficiency of combustion for emissions
• require less voltage and
• place less strain the electrical system.
I seek your input to check if my reasoning is correct on this matter.

 

[The_Eric]

Originally Posted By: LeakySeals

My understanding is its all about the efficiency of the small iridium tip. It requires less voltage to make a spark, which makes it less taxing to the coils in a modern coil over setup. Replacing a coil is not cheap. The other is the efficiency of the spark and its relationship to combusting most of the fuel in the combustion chamber. Thats good for a lot of reasons including the health of my cat. Thats what I have been told at the dealer when I asked about cheaping out on coppers. That I could get away with it, but there are potential consequences.


I would agree. I sat through a Federal Mogul tech class, and one of the things they touched on was platinum vs. iridium. Basically their thoughts were that platinum took more current to fire than iridium due to it's lower conductivity. I suppose the differences become greater when you give the iridium a fine wire tip.

As for copper core plugs, I think it boils down to longevity for the most part. In today's systems, they'll work fine, just not for as long.

 

[Trav]

Quote:
It requires less voltage to make a spark

Same with platinum. Its very easy to prove it to yourself.
Put a platinum or iridium in a lawn mower, snowblower engine with magneto ignition.

My wife could never get the push lawnmower started even when brand new because she couldn't pull it fast enough.
I put a platinum in it and she can get it going first time, every time. She noticed the difference immediately.

I run iridium's in a 3800 SC and a 3800 turbo engine with no issues whatsoever. Coil issues with iridium are non existent, they have an easier life than with standard plugs.
Platinum or iridium's are in everything i own or have worked on since before 1999 and never had a problem.

 

[Astro14]

So, Trav, you're saying I should look for Iridium plugs for the Packard then? I'll have to do some surfing...AAP doesn't exactly list the car....

 

[Vikas]

Originally Posted By: Astro14
I put Bosch Platinum plugs in my '85 Volvo 240 (intercooled turbo, K-Jetronic) and it ran worse than it had with worn copper plugs. replaced cap & rotor at the same time. Figured I must have damaged a wire while changing plugs, so replaced the wires. Still ran worse, not awful, but noticeably worse.

Changed back to copper core plugs and lo and behold, it ran better than on the Platinums.

Can't explain it, but that B21FT (Red Block for the Volvo nuts) liked copper better...


I am sorry but those were the (early) Bosch platinum days. I had exact similar experience with them on my Honda. Bosch had just come out with them. They had fancy packaging and the plug also looked extremely well made. When you look athe OEM NGK and the new fangled Bosch platinum, the Bosch just "looked" "better". I must have spent so much effort in figuring out before realizing that all my problems were because of the Bosch Platinum.

 

[440Magnum]

IMO, copper plugs actually WORK better than anything else. Copper conducts both heat and electricity far better than the rare metals, so you're less likely to get hot spots on the tip of the plug where the rare metal pellet is bonded to the copper or steel substrate. The only reason for rare metal plugs (iridium, platinum) is to make them last longer, which is a good thing for vehicles where the plugs are hard to get at. For my old big-blocks and the Jeeps, plug changes are a snap. They always get copper for maximum performance. The Ram and wife's PT get dual platinum plugs.

 

[mechtech2]

New sharp steel tips [OK, nickel alloy] are GREAT for spark!
This greatness wears off fast.
Iridium is next, followed by platinum. Precious metal tipped plugs are for longevity, not for the absolute best spark when new.

 

[DJ]

I didn't read the whole thread so maybe it was already said.

IN my stock 2005 Sierra I run stock plugs, did not even bother to look at if they were platinum or iridium, for a vehicle that sees miles the reduced electrode wear of these materials is the ticket.

Now for my street/strip 96 Caprice that has a couple full points more compression as in over 12:1 cranking compression over 240psi and runs fine on 93 octane, I need a plug a couple steps colder than stock and usually put an Autolite 103 in it. I don't leave plugs in it long enough to really wear out the basic $1.50 plug anyway and at roughly twice stock HP guys found the stock style platinum plugs to lose the platinum pucks. Say I pull the headers off once a year I go ahead and change plugs every time those are off, or maybe it begins running a little "off" for some reason so it fouls a plug. A $6 plug would be a complete waste.

Point being there are uses for many different construction types, not necessarily one is "better" than the other, sometimes they just have different strengths making them better for a particular application.

I think most of us have a few claw hammers and a few ball-pein hammers, probably at least one deadblow right? They do basically the same thing but that doesn't mean one of those hammers serves all needs.

 

[Trav]

Quote:
So, Trav, you're saying I should look for Iridium plugs for the Packard then?

If that Packard can run on no lead fuel then absolutely 100% i would run them or a double platinum plug.
Sometimes it takes a while but if you can find a modern plug number for the engine a precious metal equivalent can usually be found, even for many real old timers.
I have a friend who runs them in his 55 Caribbean and it runs much smoother and starts much easier.

There are zero advantages to a traditional copper plug other than its initial lower price tag. Even if you put no value on your time at all they are more expensive in the long run based solely on their shorter life span.

Another issue that seems to go unnoticed is the fact that due to the shorter lifespan of traditional plugs the plug wires on many engines also need to be removed more often along with the changing of the plugs.
Anyone who as turned a wrench longer than a couple of years knows the issues that can cause, loose fitting or even worse unseen separation at the terminal.

The precious metal plugs (especially the double platinum) have a life span long enough that i usually just toss the wires with the plugs.
The core of these plugs is also copper just the firing ends are precious metal plated.
Their resistance to gap erosion means the firing tip can be much finer which translates into reduced firing voltage, higher resistance to fouling. etc, etc.

These qualities are welcome in engines that use older point or magneto ignitions with lower voltage coils, were and tear on ignition components is greatly reduced.
Easier starting, less fouling, smoother idle are also traits of these plugs in addition to the qualities of a "copper" plug.

Page 2 maybe of interest to you.

http://www.ngksparkplugs.com/pdf/dyk_5points.pdf