I heard platinum spark plugs are preferable if the engine is NA mode to maximize HP and putting in iridium spark plugs will lose a HP. Is this true?

I have iridium spark plugs in and the car seems to sun smoother throughout power band. Has anyone noticed any power loss due to spark plug type change?

Thanks!

 

Iridium is better... all the new nissan 07+ 350z and 370z now have them as stock oem.

 

no it is not true. I put iridium on mine and my car actaully ran better.

 

It's been covered a hundred times.

https://my350z.com/forum/engine-and-drivetrain/257011-iridium-plugs.html

 

Here's the way I was told, regarding plugs:

Copper: Good Spark, Bad Life
Platinum: Good Life, Bad Spark
Iridium: Good Spark, Good Life, Empty Wallet

 

+1

 

mine were only $7 ea from Autozone

 

it makes zero difference as far as power is concerned. I had Iridiums in my car, and when changing coils recently, switched to OEM plugs since we had a set on the shelf....zero change in power (confirmed on the dyno)

FWIW, the NGK Iridiums cost roughly half of what OEM Nissan Platinums cost

 

who makes Nissan's?

 

NGK

 

G-r-e-a-t info', dudes! Thanks so much! The bottomline in my case is: I'll go with iridiums on the Owners' Manual's recommended heat range plug (neither a step colder nor hotter). A tune-up is a chore I wanna stay away from as long as possible, & iridium plugs cut it for me! BTW,
my Touring Coupe's bone stock.