What Is Iridium?

[sparkplugs.com]

Iridium is a precious metal that is 6 times harder and 8 times stronger than platinum, it has a 1,200 degree higher melting point than platinum and conducts electricity better.

This makes it possible to create the finest wire center electrode ever. (See "What is a fine wire plug" for information on the benefits of fine wire plugs)

Prior till now, spark plug manufacturers have favored platinum for their long life or performance spark plugs due to its high melting point. Also, the technology did not exist to machine and bond iridium on a spark plug electrode (at least in a cost effective manner).

Champion spark plugs have produced iridium industrial and aviation spark plugs since the 1960's, but they still sell for over a hundred dollars per plug. Just now is the technology cost effective to use iridium in a spark plug for automotive applications.

The strength, hardness and high melting point of iridium make it very well suited for a fine wire plug. The primary iridium plug manufacturers at this time are Denso with a 0.4mm center electrode, while Champion and NGK have 0.7mm center electrodes. These are the best performance plugs on the market for traditional automotive use and many racing applications.

SIDENOTE: Thus far the tech's we have spoken with report no problems using iridium plugs with Nitrous.

[YosemiteSteve]

Originally Posted by sparkplugs.com

Iridium is a precious metal that is 6 times harder and 8 times stronger than platinum, it has a 1,200 degree higher melting point than platinum and conducts electricity better.

This makes it possible to create the finest wire center electrode ever. (See "What is a fine wire plug" for information on the benefits of fine wire plugs)

Prior till now, spark plug manufacturers have favored platinum for their long life or performance spark plugs due to its high melting point. Also, the technology did not exist to machine and bond iridium on a spark plug electrode (at least in a cost effective manner).

Champion spark plugs have produced iridium industrial and aviation spark plugs since the 1960's, but they still sell for over a hundred dollars per plug. Just now is the technology cost effective to use iridium in a spark plug for automotive applications.

The strength, hardness and high melting point of iridium make it very well suited for a fine wire plug. The primary iridium plug manufacturers at this time are Denso with a 0.4mm center electrode, while Champion and NGK have 0.7mm center electrodes. These are the best performance plugs on the market for traditional automotive use and many racing applications.

Autolite has introduced an iridium-enhanced plug (the iridium content is too low to call it an iridium plug) we do not consider this in the same class as Denso, NGK or Champion.

SIDENOTE: Thus far the tech's we have spoken with report no problems using iridium plugs with Nitrous.

I have experience with them in some race and marine applications, is there a discount for forum members?

[sparkplugs.com]

We've been discussing a January special on iridium plugs - normally we would do a discount code for 10% off, but if we can get enough support, we could get a group buy going. PM me if you're interested in a GB in January.

[bestatchess]

Iridium is the stuff found at the K/T boundary which some scientists believe came from a big asteroid strike 65 million years ago:

http://minerals.cr.usgs.gov/gips/na/0space.htm

[92TripleBlack]

Sooo, How much and why?
Will they last 100k miles?
Will they give us better mileage?
Power?
Etc. and please quantify the answers such as 5% or 2 mpg, not answers like Yes, you can experience better mileage. A tenth of a mile on a full tank is better mileage but negledgable at the same time.
Thanks and I'm curious and interested.

[rico387]

Is iridium better than gold palladium, as once reccomended by Dr. Chistopher Jacobs?

[sparkplugs.com]

Originally Posted by 92TripleBlack

1 - Sooo, How much and why?
2 - Will they last 100k miles?
3 -Will they give us better mileage? Power? Etc. and please quantify the answers such as 5% or 2 mpg, not answers like Yes, you can experience better mileage. A tenth of a mile on a full tank is better mileage but negledgable at the same time.
Thanks and I'm curious and interested.

1 - Not sure if you're asking how much do they cost, or how much improvement will they give. In regards to cost - NGK's Iridium IX plugs (iridium center electrode, copper ground electrode) are $6.95, Denso's equivilent is $11.95. NGK also has an $11 iridium plug that has Iridium center electrode, platinum ground electrode.

2 - The manufacturers generally recommend that platinum be changed at 30k and iridium at 60k, but under normal use, they usually last a lot longer - platinums usually last at least 60k and iridium 90k plus.

3 - I know you're going to hate this answer, but "Yes, you can experience better mileage". The key is really the fine wire center electrode more so than the iridium or platinum itself. Fine wire plugs give better mileage and more power, but a copper wears too fast to make a fine wire plug out of it, so they have to use platinum and iridium tips on the fine wire plugs in order for them to last long enough. Unfortunatly, I really can't give you any hard evidence on how much power/mileage you'd gain by using iridium plugs - Plugs give different results dependant on the vehicle, mods, etc. We're about to run dyno's on an SRT-4 with new copper plugs, then new iridium plugs. But the results from that test wouldn't necessarily reflect the results you'd see by running iridiums in your Titan. Some people use iridiums for the increased power, some solely for the longivity (for example if its an all day project just getting to the plugs) I'd talk to a number of guys who've used iridiums in their Titans and ask them if they saw improvement and if they felt afterwards that it was worth the money spent.

[sparkplugs.com]

Originally Posted by rico387

Is iridium better than gold palladium, as once reccomended by Dr. Chistopher Jacobs?

Gold is an excellent conductor of electricity which makes it well suited for a performance plug. However gold is also a very soft metal, therefore the gold alloy is mixed with palladium, (a much harder metal), to form a premium fine wire performance plug with increased ignitability and durability.

Ngk's only has two gold palladium plugs (that I can think of at the moment) and they are made for powersport applications - motorcycles, race karts, etc.

[LATitan1]

Did you ever get dyno results from the SRT-4 with the Iridium spark plugs, and is iridium still the best metal on the market now getting used in Automotive plugs? What are the new E-3 plugs all about. Why can they claim more power and an increase in fuel economy? Thanks

[sparkplugs.com]

Originally Posted by LATitan1

Did you ever get dyno results from the SRT-4 with the Iridium spark plugs, and is iridium still the best metal on the market now getting used in Automotive plugs? What are the new E-3 plugs all about. Why can they claim more power and an increase in fuel economy? Thanks

Iridium is still the hardest, strongest metal being used in plugs, they haven't come out with anything yet than can top it.

Let me check on the dyno results, and I hadn't heard of the E-3 plugs before you asked - I found their website, and i'll read up on them this weekend and get back to you next week.

[LATitan1]

Thanks for your response and anxiously await your reply. Also after your investigation of these E-3 plugs let me know if Iridium is still better and what brand would you reccomend for the Titan. Trying to experiment and get slightly better gas mileage. Thanks again!

[sparkplugs.com]

I read E3's website last weekend. And it basically didn't answer any of my questions. I found a lot of fluff and performance claims, but their technical details are extremely vague. Multi-ground plugs in general shouldn't be used in any vehicle, except those made for multi-ground plugs (mostly rotary engines) and do not have any performance gains for vehicles that are not made for them, and could actually run worse. By looking at thier pictures, their version of the multi-ground plug is slightly different than standard, but they don't give a valid reason as to why their technology works and standard multi-ground plugs don't.

Only other input i have is that i have heard from those that have compared this plug with other manufacturers side by side that the quality is inferior in manufacturing and finished product. I couldn't tell you that first hand though. Although i'm sure they will be at the SEMA automotive show in Vegas this fall and i'll get to take a look.

Sounds like we need someone to try them out. Has anyone taken a shot at these plugs?

[sparkplugs.com]

As far as the dyno results are concerned, there was a slight difference on the performance between the iridium and standard nickel (aka copper) plugs, but nothing extremely drastic (he never sent me the charts so i could pull numbers). The main difference you'll see between the two plugs is longivity, and perhaps better idling. (i noticed better idling and acceleration) As far as technology is concerned, iridium fine wires are still the best plug out there. Iridium plugs only have to be changed every 60-90k miles (manufacturers claim 60k, but i've run them to 90k & beyond without a problem) where as copper plugs run for about 30k. Most people base their decision on how often they want to change their plugs out, and that will usually compensate for the extra expense of buying iridiums (except for the guys that have to put 16 plugs in their hemis)