Iridium plugs to Copper?!?! Has anyone done this?

[Lolvoguy]

Originally Posted By: Kira
I have.
2001 Chev. Camaro 3800
factory installed AC iridiums changed to AC basic plugs @ 96,000.
Noticeable boost in performance.
No data measured.


BINGO!

thanks so much for the feedback
I've purchased a set to arrive in a couple of weeks. The investment of $5.76 is a cheap price to pay. I'm planning on doing the valve cover gasket as preventative maint. (also because I'm nosey and want to see what my valve train looks like after my 5k mile OCI's using conventional).

thanks again

 

[Vikas]

You did understand that 96000 miles plugs were changed for 00000 mile plugs?

 

[DemoFly]

I wouldn't put copper in any engine that's distributor-less.

That sounds dumb.

This thread is completely anecdotal and akin to people saying BRAND NEW tires are so much better than their old tires in regards to handling and road noise.

 

[Pontual]

Originally Posted By: Kawiguy454
The electrode material is everything to due with durability and Iridium will last longer.

The heat range of a plug (heat conductivity) is adjusted by the length of the insulator cone around the electrode. Colder plugs have a shallower cone and on hotter ones the cone goes further down into the plug. The 50,000+ volts trying to make its way across the air gap could really care less what the material it is jumping across is as long as it is not a semiconductor or insulator atomically.

If you foul any set of plugs typically it is due to too much fuel and putting hotter plugs in is a wrong answer. Hotter plugs were always for keeping oil burners from fouling IMO. I hear a lot of misinformation out there.


I agree. The only exciting aspect of iridium in my case, was that the ignition improved temporarily due to the lowest impedance or resistance encontered in the iridiums sparkplugs, so a bad coil would survive a little more over iridiums since the spark jump a little easier on them, at least on their marketing speech. After it fouled, all came down together. But, in the begining, it really improved!

 

[Eddie]

I tend to think of my spark plugs as part of a developed system i.e. an ignitions system where the individual parts work together in unison. If I change a component based on guesses, I may have introduced something that will not work well within the system. I've found out with over 60+ years experience that you will not go wrong, if you replace a component in the system with a like component i.e. use the brand of spark plugs that came from the factory. Ed

 

[InvalidUserID]

I just replaced the iridium plugs in my '99 Civic with some basic copper NGKs. They'd be in for a couple years and about 40-50k. Looked OK, gap was a little bigger than spec'd but could have ran them further if I wanted.

Coppers in and no difference. Not that I was expecting any.

 

[nicholas]

Ignition coils or coil on plugs last much longer using iridium plugs compared to copper or even platinum.

All my coils that use iridium have never needed replacing - so far over 200,000kms - vs the coils that use copper or plat= around 100,000kms....

The longevity on these often expensive parts - is reason enough for me to keep using iridium in everything, with a motor, that we own = snowblower, motorcycle, lawnmower, cars.....

 

[Kestas]

I don't see how the spark plug type can affect the coil. The only variables with a spark plug that may affect the coil are resistance and gap. Gap is usually the same. So, are you saying the internal resistance of the plug is different among the types?

 

[PandaBear]

Originally Posted By: Kestas
I don't see how the spark plug type can affect the coil. The only variables with a spark plug that may affect the coil are resistance and gap. Gap is usually the same. So, are you saying the internal resistance of the plug is different among the types?


Not necessarily.

Most precious metal plugs have finer electrodes and the iridium tends to be 0.7mm dia instead of the big and wide standard "copper" plugs have. Finer firing surface reduce the voltage need so that should improve coil life and reduce misfires.

 

[Eddie]

That and the fact that spark plugs have internal resistance/impedance and that varies from type to type.

 

[SHOZ]

Originally Posted By: nicholas
Ignition coils or coil on plugs last much longer using iridium plugs compared to copper or even platinum.

All my coils that use iridium have never needed replacing - so far over 200,000kms - vs the coils that use copper or plat= around 100,000kms....

The longevity on these often expensive parts - is reason enough for me to keep using iridium in everything, with a motor, that we own = snowblower, motorcycle, lawnmower, cars.....
I switched from the standard plugs on my Accent to some iridium. 65k and no problems. But many who stay with the standard plugs burn up their COPS. I'm currently at 133k on the original coils.

And all plugs have a copper core. They have nickle, platinum or iridium plated or a pad on the actual point of the arc.

 

[Wheel]

I think the only point to iridium or platimum plugs is the extremely high melting point to save on erosion from the spark. (Particularly waste spark systems) Iridium melts at 4435 °F and platinum at 3214.9 °F. Neither evaporates until nearly 7000 degrees F.

Copper is way down at 1984 °F for melting.

Iridium's resistance is 3x that of copper. However, the spark does manage to jump the the gap anyway, even though air is over 25 times more resistant than that. Most plug wires also have more resistance than the plugs (either copper or platinum/iridium)

 

[Rhymingmechanic]

I can't speak about your particular application, but it would be interesting to see if the regular plugs increase your power and mileage as the post claims.

I did swap my '01 Silverado's stock NGK platinums for a set of plain V-Powers. I went down a heat range trying to get rid of a ping. They might have helped the ping a little, but didn't eliminate it. There was no noticeable difference in running, power, or mileage.

The gap had widened about .010 when I replaced the V-Powers with newly-specified ACDelco iridiums (also made by NGK). I do like the fact that the iridiums have been in for 40,000 miles and don't need changing any time soon. It's easy to forget about the days of 10,000 mile plug and point changes.

Back in the '90s, I put Bosch platinums in a Duster and a Caprice, both carbureted. Maybe I was just trying to convince myself the cost was worth it, but both cars seemed to run smoother. Those are the Internet's favorite plug to bash, but they seemed like an upgrade from plain old Autolites.

If you go back to iridium, shop around. I just got a set of ACDelco branded Denso iridiums from Rock Auto for a little more than $5 each.

 

[Wheel]

It is the sharp edge of the center electrode that encourages the spark across the gap. The lesser wearing iridium and platinum plugs are much finer and should have better performance over the same use as a copper plug. The erosion of the copper plugs edge will make it more difficult for an ignition system to reach the breakdown voltage of the air/fuel mix in the chamber.

I believe any new plug would help an ignition system, if the old plug was worn.

 

[andyd]

Bosch used to make a silver tipped plug for E 28s. I ran a set for 60 k miles and changed them out for plats. enge had noticeably less power. Put the silvers back in and ran them another 10K.

 

[john_pifer]

My 07 Tacoma service manual specs Cu plugs every 30K. I ran the originals until ~ 90K then switched to Autolite Iridiums.

Didn't want to bother with swapping plugs every 30K.

Interestingly, it had NGK on one side and Denso on the other side from the factory. I posted photos here when I did it - the Densos looked a lot better to me after pulling them.

 

[wtd]

I have two 98 chevy trucks, one with the 5.7L and one with the 7.4L. The original plugs were double platinums. I was running single platinum Delco Rapidfire plugs. I recently installed the newly recommended Delco iridium plugs and both trucks feel like they have more power and have an smoother idle. The plugs that I took out of both trucks were not in there very long because the recommended Rapidfire plugs for both trucks were no longer the ones that were in there.

This gave me a reason to try out the iridium plugs and I like them.

Wayne

 

[Lolvoguy]

Finally got around to changing the plugs to the coppers.
I also did the valve cover gasket as it's a common problem as the old one ages, it allows oil to enter the plug tubes. For an additional $16 bucks, I couldn't go wrong.

Well, after a test drive I've noticed noticeably less NVH. The idle is smoother as well as acceleration. Engine seems to struggle a little less. I'm interested to see if I get any increases in fuel economy.

OTOH, the original iridium plugs had a good 80k miles on them. So replacing them with anything would be an improvement. I guess they arent' a 100k miles plug afterall

 

[blupupher]

I did on my '02 Elantra. At 60,000 miles I replaced the OEM Champion Platinum with some Autolite copper plugs. I also changed the plug wires. No difference in how it ran, mileage or butt dyno.
Old plugs were still in good shape. Changed the copper plugs 2 more times with copper plugs (every 30,000 miles) and never had an issue.

 

[Gokhan]

Copper?? There is no such thing as a copper-tipped spark plug. Copper has a low melting point and it wouldn't last an hour in an engine. What NGK means by copper is that they have copper cores, not copper tips. Standard spark plugs come with nickel-alloy tips, which have high melting temperature. I believe most spark plugs have copper cores, regardless of the tip (standard [nickel], platinum, or iridium).

The reason they use copper cores is for better thermal conduction, not for better electrical conduction. There is a 5,000-ohm series resistor inside the copper core in virtually all spark plugs to greatly reduce radio-frequency (RF) interference. You can simply test this using an ohmmeter between the plug connector and center electrode. Without it, your ignition system would act as a radio transmitter, such as the spark-gap radio transmitters they used to have in the past. So, a-tiny-friction-of-an-ohm difference between copper, nickel, platinum, and iridium is a nonissue.

I don't know which is better -- standard (nickel), platinum, or iridium. I would go with OEM for peace of mind.

Here is what Toyota says about spark plugs used in their most state-of-the-art engine -- 2016 Prius:

From what I read, iridium has higher ignition performance than platinum and platinum has higher ignition performance than standard (nickel). The general claim made is that the thinner the electrode, the higher the ignition performance is. The thickness of the electrode is limited by the melting temperature; so, iridium is the thinnest (highest performance) while nickel (standard plug tip) is the thickest (lowest performance).

This said, I still use standard OEM DENSO nickel plugs for peace of mind and change them in no more than 30,000 miles, usually a lot less. DENSO makes various alternatives to the standard plug, including iridium twin-tip (TT), which has both the center and ground electrodes as iridium needles.