A Question about spark plugs

IN GENERAL, which type of spark plug delivers the best engine Performance ?

1. Copper

2. Platinum

3. Double Platinum

4. Iridium

5. Other (if they exist IDK)

In the above choices, plug life increases from top to bottom, but your answer should ignore the projected life of the plug, and should also ignore any specific applications for specific cars. Your answer should consider the analysis in terms of engine/vehicle Performance only other things being equal. Your answer should also assume regular gasoline cars and light truck daily drivers, no diesels, heavy duty commercial, high performance sports cars or supercars, bikes etc. I am also not concerned about gas mileage if that makes any difference.

Of course if I'm asking the wrong question out of ignorance that's fine, answer any way you wish. And if you're a rebel like me you may also answer the question any way you like. Any and all spark plug knowledge and wisdom from mechanics, engineers, smart dudes, aircraft pilots, astronauts, or regular joes like me on the great Sigforum Brain Trust, as always, are greatly appreciated. Any answers from Politicians representing the Democratic party will be summarily ignored and severely reprimanded.

My spark plug knowledge is limited, still stuck in the 60s and 70s with hot/cold vs resistor/non resistor AM radio noise cancelling etc. When it comes to my daily drivers I always want to set them up for the best performance possible with normal factory specs but using higher than normal quality parts like Bilstein shocks, premium synthetic motor oils, specific radiator fluids, OEM quality bolt-ons and brakes etc. I'm not a racer or motorhead, but I work on five vehicles that operate out of my household and it's a hobby and a way I relax when at home after work.

Iridium.

Iridium is the longest-lasting. But one type won't generate any hotter or better spark than another. Don't be fooled by the claims of "gimmick" spark plug makers that it will. If your car uses copper-core and you put iridiums in it, it won't run any better. In fact, sometimes it will run worse. I have found that it is best to stick with the same brand/type as what came with the car. IOW, Champions for Chrysler, Motorcraft (Autolite also OK) for Ford, AC/Delco for GM, Denso (NGK also OK) for Asian.

Yep, Iridium. It's what My Sorento uses and they are supposed to last for 100k miles.

Jim

My 300ZX TT calls for twin platinum, so that is what it gets.

I've always used the same that came from the factory. In my cars/trucks, boats, motorcycles, and lawn equipment. Never had a problem.

I'd go with the Iridiums and a tube of antiseize just so I won't have to change them as often.

Iridium
They are good for 100.000 miles. My truck has 88,000 and I changed them just because I had the time. They looked very good. I also just put them in my sons 2010 Honda Civic at 96,000 miles. Again they looked good. They were the recommended plug for each vehicle.

Use whatever the manufacturer used from the factory. There's almost no performance improvement changing the spark plug type from factory spec unless the engine is highly modified.

In fact, you can hurt engine performance if you choose wrong.

For today's cars use what the factory puts in them. There are too many variables to account for with spark plugs to get the best out of your car.

There is no magic spark plug that will give you better performance or MPG.

The only caveat to that is modified engines and I'm talking more than just a different intake/exhaust.

No plug increases performance in anything that has a remotely stock (meaning today's emissions) engine. Period.
However changing them is PIA in just about every motor so go long life.

quote:

Originally posted by hrcjon:
No plug increases performance in anything that has a remotely stock (meaning today's emissions) engine. Period.
However changing them is PIA in just about every motor so go long life.

In almost every fwd 4 cylinder car, changing plugs takes 15 minutes.

Scurvy does not have a Hemi.

If the performance of the spark plug is to be measured in electrical "spark" performance, than copper is better than all of them. Why? Simply because of conductivity. Unfortunately, copper has the down side of wearing out (eroding) faster and needs to be changed out more often. However if you are shooting for peak engine "spark" performance over the shorter term (like in a race dirt bike), then copper is the best material.

If spark plug performance is to be measured in terms of not-having-to-change periods, then the platinums, iridiums, etc beat copper hands down.

quote:

Originally posted by GT-40DOC:
My 300ZX TT calls for twin platinum, so that is what it gets.

What year is your TT ?? I have one too God Bless

Platinum and Iridium for longevity. Platinum is made to last approx. 40-60K miles, whereas Iridium is 80-100K miles. Someone please correct me if I am wrong. God Bless

No performance improvement.
I use whatever factory calls for but change them at 1/2 the interval the factory calls for.
Cheap and easy.
For me Factory calls for 100k change and .035 gap. No way I’d ever go that long.

quote:

Originally posted by Scurvy:
Use whatever the manufacturer used from the factory. There's almost no performance improvement changing the spark plug type from factory spec unless the engine is highly modified.

In fact, you can hurt engine performance if you choose wrong.

This. The engine in my Jeep was designed for copper plugs and doesn’t run well on platinum or iridium plugs.

My van, however, was designed for platinums but the spec changed to iridium a year or so later. And it’s worth it, considering how much fun it is to change the plugs on that thing.

No magic one size fits all plug; different engines work better with different plugs.

My understanding is when you refer to a copper plug, it means a copper conductor within the plug, and likely a steel electrode. Platinum and iridium plugs have either a disc of that metal welded to one or both of the electrodes, or sprayed on as plasma. These metals are resistant to erosion and maintain gap longer.

As far as which one performs best in a particular engine, electrode material may not be the biggest factor.

quote:

Originally posted by Xer0:
If the performance of the spark plug is to be measured in electrical "spark" performance, than copper is better than all of them. Why? Simply because of conductivity. Unfortunately, copper has the down side of wearing out (eroding) faster and needs to be changed out more often. However if you are shooting for peak engine "spark" performance over the shorter term (like in a race dirt bike), then copper is the best material.

If spark plug performance is to be measured in terms of not-having-to-change periods, then the platinums, iridiums, etc beat copper hands down.

This. If you don't mind changing them regularly you can't get better performance than copper. Having said that, I generally run Platinum or Iridium.