tropic said:
PLATINUM VS. IRIDIUM
- Thread starter MADMIKE
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Kestas
Staff member
Do any manufacturers make the best of both worlds and use copper core AND Pt or Ir tips? It would sure make a better plug than the fancy ones with multiple tips.
If any of you are REALLY interested in documented and independent testing data go to the SAE site and order paper number 2006-01-0224, 'The Effect of Sparkplug Design on Initial Flame Kernel Development and Sparkplug Performance
A car ran better with new spark plugs - well, what else would happen ?
It is then attributed to whatever we choose as the key factor.
It is then attributed to whatever we choose as the key factor.
I want to restate that iridium and platinum plugs last a long time, compared to steel tipped plugs.
But iridium has a bit better conductivity [and usually higher cost].
But iridium has a bit better conductivity [and usually higher cost].
Sorry that is what I meant. Somewhere on the NGK site there is a picture (electron microscope?) that shows the difference.
over on the neons.org webiste, some have questioned platinum and iridium, in plymouth neons, compared to stock coppers. The result.. was to stay with coppers. Why/ Because its an interface? engine, waist spark system. One neon mechanic, upon engin teardown, and using iridiums, noticed alot of carbon deposits built up on his pistons..his conclusion, was it was the Iridiums that casued it. 2 other mechnics, using platinums, discovered around 20,000 miles, hte platinum electrode, was eroded/completely gone. I myself have seen this, in my sisters finace's sisters car, early this year... chnaged her pulgs in a 97 ford taurus. They were motorcraft platinums, and the electrodes were completley gone! 6 cylinder car. I was in Awe it still ran!
Just some stuff i learned, and thought too share with all
Just some stuff i learned, and thought too share with all
The key conclusion was, from all neon mechanics..
Just get the cheap coppers.. you should change them every 15,000 miles or 2 years, bu they will ensure proper spark and running condition, rather than taking yuo chances with platinums.
Just get the cheap coppers.. you should change them every 15,000 miles or 2 years, bu they will ensure proper spark and running condition, rather than taking yuo chances with platinums.
Platinum plugs were the first long life plug material. On many modern cars it is very difficult to change spark plugs due to the intake manifold design. Iridium plugs are the latest in long life spark plug design. They also make Iridium "performance" plugs that have a smaller electrode which gives slightly better performance with a trade-off in a shorter life span.
In general;
true double-platinum sparkplugs last about 60k miles.
true long-life irridium spark plugs last about 100k miles.
In order to be a true long-life plug, they need to have a chunk of platinum on the ground electrode.
In general;
true double-platinum sparkplugs last about 60k miles.
true long-life irridium spark plugs last about 100k miles.
In order to be a true long-life plug, they need to have a chunk of platinum on the ground electrode.
I had also seen an add in magazine, where thiers a spark plug yu can buy,m that uses a laser? I forget what its called, but it does have a website. Expensive too... it was like $50 a plug i think/
At 40K I changed out the plugs in the TL trying to trace down a detonation problem. I couldn't find one heat range colder with the factory Iridiums so I had to go with platinums. I noticed cold idle was better with the new plugs but that might have been because they were new, regardless of what material they are coated with. I do know one thing, idle improved, at least when cold so that leads me to believe that while iridiums may last 105,000 miles (the TL's first factory recommended tuneup) you're probably not getting peak performance anymore.
On a side note, I just about had to use a breaker bar to get them out. Glad I didn't go the entire 105K. The new ones went in with anti-sieze.
In the turbo cars, a lot of us noticed detonation with platinum plugs when running high boost, not so much with sane levels of boost. I could tune it to the edge of detonation on pump gas and 17psi boost with no problem with a normal copper plug or platinum. But at boost pressures in excess of 25psi I could switch the coppers for platinums with no other changes and it would detonate. I was not the only one who noticed this.
On a side note, I just about had to use a breaker bar to get them out. Glad I didn't go the entire 105K. The new ones went in with anti-sieze.
In the turbo cars, a lot of us noticed detonation with platinum plugs when running high boost, not so much with sane levels of boost. I could tune it to the edge of detonation on pump gas and 17psi boost with no problem with a normal copper plug or platinum. But at boost pressures in excess of 25psi I could switch the coppers for platinums with no other changes and it would detonate. I was not the only one who noticed this.
The NGK iridium IX uses lasers to weld for smaller smooth seams and they are $8 each
NGK why plugs get fouled
and the electrode looks like a paperclip hehe i'm running em
NGK why plugs get fouled
and the electrode looks like a paperclip hehe i'm running em
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Originally Posted By: heathenbrewing
Conventional spark plugs generally last one year. Platinum or iridium can last, depending on manufacturer specifications, up to seven years. Why anyone would consider leaving plugs in for 7 years is beyond me though. A brand new copper plug will outperform a 6 month old PL or IR plug.
Do you realize that you contradicted yourself in your statement?
A brand new standard plug will not outperform a 6 month old PL or IR plug. why? well, the gap erodes at least 7 times slower on an IR plug, IR plugs require less voltage to fire and have a more stable spark.
Now think about price. If I have a 4 cylinder engine and I use the 2 dollar standard plugs, then it will cost me 8 bucks a year for plugs, not bad per say.
On the other hand, IR plugs last at least 7 times longer than the standard plugs. So do the math, 7 years worth of standard plugs will cost me 56 bucks, but if I buy the IR plugs I end up paying 32 bucks(8 dollars a plug). That gives me 24 more dollars in my pocket and less labor (not that its strenuous work, but still...its less wear and tear on the engine's head).
Who knows? Every engine is unique. If standard plugs work for you, then by all means keep using them. I just presented my opinion and don't expect you agree.
Conventional spark plugs generally last one year. Platinum or iridium can last, depending on manufacturer specifications, up to seven years. Why anyone would consider leaving plugs in for 7 years is beyond me though. A brand new copper plug will outperform a 6 month old PL or IR plug.
Do you realize that you contradicted yourself in your statement?
A brand new standard plug will not outperform a 6 month old PL or IR plug. why? well, the gap erodes at least 7 times slower on an IR plug, IR plugs require less voltage to fire and have a more stable spark.
Now think about price. If I have a 4 cylinder engine and I use the 2 dollar standard plugs, then it will cost me 8 bucks a year for plugs, not bad per say.
On the other hand, IR plugs last at least 7 times longer than the standard plugs. So do the math, 7 years worth of standard plugs will cost me 56 bucks, but if I buy the IR plugs I end up paying 32 bucks(8 dollars a plug). That gives me 24 more dollars in my pocket and less labor (not that its strenuous work, but still...its less wear and tear on the engine's head).
Who knows? Every engine is unique. If standard plugs work for you, then by all means keep using them. I just presented my opinion and don't expect you agree.
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+1
Down_South
I ran my OEM Denso PK20R-11 plugs for 160K
I'm on my 3rd set, the 2nd set was in for about 65K. I last changed them at the 221K mark, I'm at 232 now.
I'm on my 3rd set, the 2nd set was in for about 65K. I last changed them at the 221K mark, I'm at 232 now.
There is no exact mileage set in stone, but your Manufacturer sets out a mileage that works best over an average set of conditions and climates. Also running a plug too much longer than is recommended by your OEM or by the Manufacturer of the plug can put undue stress on your coil packs and you could be looking at replacing them.
To me changing the plugs when they are called for is cheaper than a coil pack... But good to know nthach that they last that long!
To me changing the plugs when they are called for is cheaper than a coil pack... But good to know nthach that they last that long!
Just wondering. If you regap a platinum plug every 30k miles, can you keep using it beyond the 90k typical life?
I'm trying to do that right now with mine.
I'm trying to do that right now with mine.
I've already given my .02 a bunch of posts up.
In short, while the irridiums may still work at extreme mileages, it doesn't mean they're at their peak performance. I swapped my factory irridiums with platinums at 40K and noticed an improved cold idle. It's going on another 40K and hopefully they now make an irridium plug one heat range colder now so I can go back to them.
I think it's good to swap the plugs at sane intervals because you can see if a cylinder is having problems such as oil burning, lean/rich, detonation, etc. Then there's the danger of stripped aluminum heads with 100K+ intervals.
In short, while the irridiums may still work at extreme mileages, it doesn't mean they're at their peak performance. I swapped my factory irridiums with platinums at 40K and noticed an improved cold idle. It's going on another 40K and hopefully they now make an irridium plug one heat range colder now so I can go back to them.
I think it's good to swap the plugs at sane intervals because you can see if a cylinder is having problems such as oil burning, lean/rich, detonation, etc. Then there's the danger of stripped aluminum heads with 100K+ intervals.
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