Iridium Spark Plug Maintenance

I upgraded to either Denso or NKG (can't remember) iridium tip spark plugs at 30k miles. I'm now at 60k+, and was wondering whether I still need to swap out the plugs since I've upgraded to iridium? If no one knows that answer, then:

What is the spark plug maintenance cycle for folks who have the TRD Supercharger? I will just follow that cycle then.

 

Iridium plugs are normally good for 100k.

 

They last longer than the standard plugs...definitely longer than 30k...I think they are usually good for 100k

 

I wouldn't worry about it until 80 to 100K as long as I didn't notice any issues.

 

Thanks for the responses guys - I'll leave them be for now. Make next summer I'll swap them then.

 

Are you supercharged? If not then they should last you to at least 80k I would think. If I remember correctly, supercharged applications have to change them out at around 60k.

 

No, not supercharged, yet . Maybe once I make a case my wife that it saves fuel or some other backwards fabricated BCA, heh heh heh.

So the derived recommendation here is... If you are not supercharged and have iridium plugs, then it's acceptable to go to between 80k to 100k miles. If you are supercharged, then change them out every 60k miles.

The benefit of going with iridium is not having to swap spark plugs every 30k miles.

 

Another added benefit of Iridium is that if you are supercharged, the engine performs much, much better. I learned this the hard way. Stock copper plugs cause spark knock like crazy, colder iridium plugs = no spark knock.

Also, saying that the supercharger 'saves fuel' doesn't necessarily have to be a lie...it can actually be true. Technically speaking, a supercharger makes an engine run much, much more efficiently. Only reason it causes MPG's to go down is because people tend to go wide open throttle with it to get all of the added power. That'll kill your gas mileage even if you're not supercharged. If you drive normally with a supercharger installed, you can actually see better MPG. I get great mileage if I'm driving carefully with my s/c. If I decide to have some fun with it, well....that's another story, haha.

 

The 2.7L come with iridium plugs from the factory. The factory maintenance for the spark plugs is 120k miles.