Iridium Spark Plugs

[MattAlpha]

My 96 XJ Sport is mostly stock, though I try to replace all my OEM equipment with performance equipment when I need to or I have some extra cash.
I'm looking to replace my set of Bosch Platinum2 spark plugs with an Iridium set. The Bosch set works fine, but I'd like to try out the Iridium ones due to the tech stuff I've been reading about them. Unfortunately I can't find an Iridium plug to replace standard OEM plugs made by NGK, DENSO or Champion.
Does anyone know of an Iridium plug that will work in my L6?
Thank you in advance!
-Matt

 

[Dragon_Fly]

Denso and NGK are the same company... like GMC and Chevy... NGK makes some plugs for others like AC-Delco platinum plugs and some of those are actually iridium but are listed as platinums and only are half the cost.

Iridium plugs are top of the line.... they have the advantage over platinum just like platinums have over conventional plugs. They are like 6 times harder then platinum and allow the transfer of electrons much easier which means it doesnt take as much energy to produce a spark. They wear longer then platinums and over a period of the life of the plug they are more efficient. Even with all these benefits I can't see paying 12-18 bucks per plug. If you have a forced induction engine then they are worth the money.
If you still want them I can find the part number needed for your year... or you can check out autozone as they carry them or can order them.

 

[MattAlpha]

Dragon Fly,
Thank you for the advice. I didn't know that NGK made plugs under other companies' names.
I searched the online part stores (Advanced Autoparts, AutoZone, NGK website, champion website and a few online parts brokers), but none of them had any type of Iridium plugs for my XJ.
Is there a specific part name that NGK runs their cheaper Iridiums under when they are so-called platinums?
Thank you for your assistance.

 

[Dragon_Fly]

For me Denso and NGK are synonymous. I trust either plug. They are made the same way. I know they carry them for my year of XJ. Soonest I could check would be Sunday.
Here's something to look at until then:

http://www.densoiridium.com/index.php
http://www.ngkiridium.com/

I know the PN isnt listed... but I am still going to check into it. Ofcourse I have no affiliation with either company. And I think the P2's you are using are very well suited for our application. It is only my opinion the iridiums are overkill for the L6's.

 

[MudDawg]

I have used NGK plugs almost exclusively for 31 !!!!!! years. The biggest advantage of iridium is it's ability to withstand heat without erosion. Very good plugs for use in motors run with extreme turbo boost or extreme nitrous loads.

 

[Dragon_Fly]

Matt... forgot to add about the plat plugs being iridiums... these are for the newer vehicles... they are listed as being platinum plugs but are actually NGK Iridium plugs. They part number says its a platinum plug but written on the side of the plug is NGK Iridium. Some are AC-Delco but are really rebadged NGK plugs.

 

[MattAlpha]

Dragon Fly thank you again for your assistance.
MudDawg thanks for the advice, I'm not running NO2 and I don't plan on it.
-Matt

 

[FUNKYTEE5]

My 96 XJ Sport is mostly stock, though I try to replace all my OEM equipment with performance equipment when I need to or I have some extra cash.
I'm looking to replace my set of Bosch Platinum2 spark plugs with an Iridium set. The Bosch set works fine, but I'd like to try out the Iridium ones due to the tech stuff I've been reading about them. Unfortunately I can't find an Iridium plug to replace standard OEM plugs made by NGK, DENSO or Champion.
Does anyone know of an Iridium plug that will work in my L6?
Thank you in advance!
-Matt

From what i've heard the iridium plugs are very durable and long lasting. The guys running high boost applications have benefited from these plugs because the electrode is very small, in turn concentrating the spark to jump from the same single spot. With high boost situations there is far more air/fuel mixture in the chamber as compared to a naturally aspirated motor. This higher concentration of air/fuel in between the plug gap creates far more resistance for the spark to find it's way across the gap producing random misfires. With high boost, a powerful ignition is crucial to keeping misfires at bay. In a stock motor without boost, you may not get any gains. After all, your plugs will only spark as much as your coil can put out! I would suggest to put the money into other bolt on's that will produce proven gains! If your spark is good, then focus on improving the efficiency of the motor! The 4.0 has plenty of potential! Half of the guys I know running at the strip use .99 cent Autolites and one of em runs a street driven Chevelle that does 10.60's 1/4 mi. all day long! I run them too and I usually replace them once every 1-1/2 years or so. 6 or 7 bucks for new plugs! That's what i'm talking about! Put the money where it counts. Good luck.

FUNKYTEE5

 

[MattAlpha]

Thank you FunkyTee5.
Listening to you all, I'm just going to stick it with what I know works well. I got another set of the Platinum 2s and there as good as ever.
Thanks again for everyone's advice!
Matt

 

[Wolf]

Half of the guys I know running at the strip use .99 cent Autolites and one of em runs a street driven Chevelle that does 10.60's 1/4 mi. all day long!

:yelclap: That's my take too. Buy the Autolite coppers, change them when you change the oil, and you'll likely see better performance than you would with the expensive plugs changed less frequently.