overpriced exotic metal spark plugs that underperform!!

And yet there are no copper electrode plugs. How does that work? What is conducting better?
I suppose the larger diameter of a "copper" plug electrode could conduct more amps more easily? I see a plug experiences 20-30 amps for a short amount of time, which is significant for a long wire of centre electrode diameters, under constant loads. But what relevance that is for spark plugs, I don't know, probably not much given the number of small centre electrode plugs available, and they all are very short anyways...

There must a be a serious spec engine race series somewhere with street car levels of engine performance, where spark plugs are unregulated, and then someone will have figured out, if any plugs make even a 0.5% difference. And then that might be specific to that engine...
 
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On thr subject of overpriced.

At my local Mazda dealer plug are $50 for one plug.
I can't even find plugs for my wifes 2024 CX-5 or my 2023 Mazda 3. Same engine. Code M. Cylinder deactivation. ONly plug available is through the dealer. I think they're like $ 30 each at my dealership and have to be done every 60K or every 75K. I would have to look it up. Luckily, both cars are under 15K, so not an immediate issue.

I have seen ZERO aftermarket plugs for the skyactive engines (later models anyway.)
 
I suppose the larger diameter of a "copper" plug electrode could conduct more amps more easily? I see a plug experiences 20-30 amps for a short amount of time, which is significant for a long wire of centre electrode diameters, under constant loads. But what relevance that is for spark plugs, I don't know, probably not much given the number of small centre electrode plugs available, and they all are very short anyways...

There must a be a serious spec engine race series somewhere with street car levels of engine performance, where spark plugs are unregulated, and then someone will have figured out, if any plugs make even a 0.5% difference. And then that might be specific to that engine...
But, there are no copper electrodes!

That misconception is the entire crux of the confusion in this thread. All of the spark plugs have copper in their core and that handles most of the conduction of electricity down to the tip.

The electrode.

And that tip has to be of a high enough melting point to survive in an engine.

Go pick up a set of “copper“ plugs, and tell me what material is used in the electrode.

Because I will bet my next paycheck, that the electrode is not copper.

Even in 1932, with 6 V ignition systems, using coil windings, and points ignition with capacitor (called a condenser) those spark plug electrodes were nickel.

Not copper.

The larger size of the electrode is actually a disadvantage. You get a better spark, a larger kernel, from a smaller electrode.

There is no advantage to “copper” plugs with a nickel electrode other than cost.
 
But, there are no copper electrodes!

That misconception is the entire crux of the confusion in this thread. All of the spark plugs have copper in their core and that handles most of the conduction of electricity down to the tip.

The electrode.

And that tip has to be of a high enough melting point to survive in an engine.

Go pick up a set of “copper“ plugs, and tell me what material is used in the electrode.

Because I will bet my next paycheck, that the electrode is not copper.

Even in 1932, with 6 V ignition systems, using coil windings, and points ignition with capacitor (called a condenser) those spark plug electrodes were nickel.

Not copper.

The larger size of the electrode is actually a disadvantage. You get a better spark, a larger kernel, from a smaller electrode.

There is no advantage to “copper” plugs with a nickel electrode other than cost.
I think Auburn Manufacturing makes one for their equipment? Side electrode anyway:

https://www.grainger.com/product/62...pyZUDcYORCfrJEk21jhoCCNYQAvD_BwE&gclsrc=aw.ds


Link above says they couldn't find it, but if you click it, it works. Weird...

I'll DM you my banking information.

:)
 
But, there are no copper electrodes!

That misconception is the entire crux of the confusion in this thread. All of the spark plugs have copper in their core and that handles most of the conduction of electricity down to the tip.

The electrode.

And that tip has to be of a high enough melting point to survive in an engine.

Go pick up a set of “copper“ plugs, and tell me what material is used in the electrode.

Because I will bet my next paycheck, that the electrode is not copper.

Even in 1932, with 6 V ignition systems, using coil windings, and points ignition with capacitor (called a condenser) those spark plug electrodes were nickel.

Not copper.

The larger size of the electrode is actually a disadvantage. You get a better spark, a larger kernel, from a smaller electrode.

There is no advantage to “copper” plugs with a nickel electrode other than cost.
I don't have a dog in this fight, but it is interesting that people still claim nickel "copper" electrode plugs produce slightly more power in road cars at least. I'm just interested if there could be a kernel of truth to it?
I will agree that for normally driven road cars, running platinum or iridium plugs makes the most sense.

But it seems the plug issue is sufficiently complicated that the answer for maximizing performance starts with "it depends" :LOL:
https://www.enginebuildermag.com/20...nd NASCAR have,screws into the cylinder head.
Another metal that is used for the tip of the center electrode in some racing plugs is silver. Silver conducts electricity three times better than iridium, and six times better than platinum. This helps to increase the current across the electrodes when the plugs fire for a more reliable spark. The drawback with silver is its low melting point and lack of wear resistance compared to iridium or platinum. Silver plugs will only last about 20,000 to 30,000 miles in a motor.
Going by this, maybe there is a chance that a larger nickel electrode could have more conductivity at least, as nickel is also a better conductor than platinum, and not that far off of iridium, so with a larger diameter centre electrode, it may be possible it conducts more? I've read somewhere that higher amperages are mostly carried on the outside of a surface of a wire, so a larger diameter centre nickel electrode maybe significant at 20-30 amps a spark peaks at? It would be for a constant 30 amps over a longer distance for sure.
 
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The core of the plug is copper. The electrode is what we are discussing. Even ruthenium plugs have copper cores.

Silver conducts even better than copper. Gold better still. So, why not silver or gold plugs? Because they would cost too much.

The electrode material matters. But melting point is the critical factor.

Iridium, and ruthenium, have exceptionally high melting points. Platinum is close. So, those electrodes don’t erode nearly as quickly as nickel, which has a good melting point, but not as high as those others.
Correct, not debating that, it wasn't a longevity discussion. And yes silver and gold is better but as stated more expensive. Longevity is the reason for iridium and ect making the electrode lasting longer. The stated gains w copper plug was specific to that, it conducts/more efficient for non precious metals would be the reason for it.
I use what was oem and works fine without using a newer tech plug. I don't mind changing plugs at 30k, 50k or sooner if need be, so I don't care for using different. Use your iridium, ruthenium or whatever you wish not stating not to.
 
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I can't even find plugs for my wifes 2024 CX-5 or my 2023 Mazda 3. Same engine. Code M. Cylinder deactivation. ONly plug available is through the dealer. I think they're like $ 30 each at my dealership and have to be done every 60K or every 75K. I would have to look it up. Luckily, both cars are under 15K, so not an immediate issue.

I have seen ZERO aftermarket plugs for the skyactive engines (later models anyway.)
I'm running NGK Ruthenium HX LKAR7AHX-S in my 16 CX-5.
 
I don't have a dog in this fight, but it is interesting that people still claim nickel "copper" electrode plugs produce slightly more power in road cars at least. I'm just interested if there could be a kernel of truth to it?
I will agree that for normally driven road cars, running platinum or iridium plugs makes the most sense.

But it seems the plug issue is sufficiently complicated that the answer for maximizing performance starts with "it depends" :LOL:
https://www.enginebuildermag.com/20...nd NASCAR have,screws into the cylinder head.

Going by this, maybe there is a chance that a larger nickel electrode could have more conductivity at least, as nickel is also a better conductor than platinum, and not that far off of iridium, so with a larger diameter centre electrode, it may be possible it conducts more? I've read somewhere that higher amperages are mostly carried on the outside of a surface of a wire, so a larger diameter centre nickel electrode maybe significant at 20-30 amps a spark peaks at? It would be for a constant 30 amps over a longer distance for sure.
Yep, it always "depends."
 
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And yet there are no copper electrode plugs. How does that work? What is conducting better?
Go ask the auto industry, they named it copper plugs not me. So go argue it with them. And for the non precious metals copper conducts/more efficient than most, as I am sure you are aware of.
 
I'm running NGK Ruthenium HX LKAR7AHX-S in my 16 CX-5.
Just found this when I was googling what Ruthenium was. I'm sure they are good plugs, but when manufacturers start making graphs like this, I start thinking snake oil... Seems like made up poorly thought out marketing graphics...
If NGK was a small company starting out, this sure as heck wouldn't encourage me to buy their stuff.
NGK68716-graphics-for-web-ACCELERATION-768x384.webp

https://ngksparkplugs.com/en/produc...ional spark,more stable with less dispersion.
 
I don't have a dog in this fight, but it is interesting that people still claim nickel "copper" electrode plugs produce slightly more power in road cars at least. I'm just interested if there could be a kernel of truth to it?
I will agree that for normally driven road cars, running platinum or iridium plugs makes the most sense.

But it seems the plug issue is sufficiently complicated that the answer for maximizing performance starts with "it depends" :LOL:
https://www.enginebuildermag.com/20...nd NASCAR have,screws into the cylinder head.

Going by this, maybe there is a chance that a larger nickel electrode could have more conductivity at least, as nickel is also a better conductor than platinum, and not that far off of iridium, so with a larger diameter centre electrode, it may be possible it conducts more? I've read somewhere that higher amperages are mostly carried on the outside of a surface of a wire, so a larger diameter centre nickel electrode maybe significant at 20-30 amps a spark peaks at? It would be for a constant 30 amps over a longer distance for sure.
You are discharging the coil through the plug and it's the voltage (why ignition coils are high voltage) to bridge the gap that's the requirement for the spark. A larger gap will require higher voltage. Also, it's not 20-30 amps through the plug, it's like 50mA, 20-30A would be instantly lethal if you were to accidentally touch a plug lead. Many modern ignitions fire the plug multiple times at low engine speeds (like how the old MSD boxes worked) to improve ignition and reduce emissions.

When a plug fires; when the spark jumps the gap, there's a "kernel", it's basically the area directly around the spark, that aides in igniting the mixture. Common hotrodding "trick" was to cut back the strap to expose more of the centre electrode to make the kernel bigger. This was the same though process behind the Splitfire plugs, the Bosch +4 plugs...etc. Expose the kernel, improve the ignition of the mixture. People also indexed their plugs so that the open side was pointing toward the intake valve and into the chamber with the strap toward the wall (on wedge chambers).

Also, if you are racing, you are changing the plugs regularly. Spending extra money on plugs designed to last 100,000 miles would be a complete waste.
 
You are discharging the coil through the plug and it's the voltage (why ignition coils are high voltage) to bridge the gap that's the requirement for the spark. A larger gap will require higher voltage. Also, it's not 20-30 amps through the plug, it's like 50mA, 20-30A would be instantly lethal if you were to accidentally touch a plug lead. Many modern ignitions fire the plug multiple times at low engine speeds (like how the old MSD boxes worked) to improve ignition and reduce emissions.

When a plug fires; when the spark jumps the gap, there's a "kernel", it's basically the area directly around the spark, that aides in igniting the mixture. Common hotrodding "trick" was to cut back the strap to expose more of the centre electrode to make the kernel bigger. This was the same though process behind the Splitfire plugs, the Bosch +4 plugs...etc. Expose the kernel, improve the ignition of the mixture. People also indexed their plugs so that the open side was pointing toward the intake valve and into the chamber with the strap toward the wall (on wedge chambers).

Also, if you are racing, you are changing the plugs regularly. Spending extra money on plugs designed to last 100,000 miles would be a complete waste.
Wait till they hear about what temperature rating of a plug does.
 
But the firing surface isn't copper, so that's a red herring, it's nickel, as others have already said.
Not arguing that it isn't, never once said that it wasn't, calling it copper is the standard terminology for it. Ague the point with whomever named it not me.
 
Not arguing that it isn't, never once said that it wasn't, calling it copper is the standard terminology for it. Ague the point with whomever named it not me.
Again, you stated:
wlk said:
And for the non precious metals copper conducts/more efficient than most, as I am sure you are aware of.
What point is it you are trying to make here then, if you are acknowledging that "copper" plugs aren't in fact copper? I'm arguing with you, because you just made that statement.
 
Again, you stated:

What point is it you are trying to make here then, if you are acknowledging that "copper" plugs aren't in fact copper? I'm arguing with you, because you just made that statement.
The point was the copper plug created a few extra hp. The copper plugs were more efficient at transferring the electricity to the plug, gaining the extra power. Whether the tip is nickel and not actual copper doesn't matter it performed better as the test was a dino not the longer last tips. No aha moments here just the fact that the copper was better at conducting the energy, period. Or if you prefer to call it a nickel plug go ahead.
 
The point was the copper plug created a few extra hp. The copper plugs were more efficient at transferring the electricity to the plug, gaining the extra power. Whether the tip is nickel and not actual copper doesn't matter it performed better as the test was a dino not the longer last tips. No aha moments here just the fact that the copper was better at conducting the energy, period. Or if you prefer to call it a nickel plug go ahead.
I don't think the power difference is from what you believe it was from.
 
Maybe, maybe not, you have zero clue of my understanding but I don't care, it is not that important
You gave plenty of clues. "The copper plugs were more efficient at transferring the electricity to the plug, gaining the extra power."
 
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