Just wondering what spark plugs people are using out there and if there's really a difference between some of the more expensive ones.

 

stock iridiums

 

Iridium is what you should use. They will last you up to 100K miles. You can use stock or any other brand.

 

NGK or Denso Iridium should be your only consideration. Boosted I run 2 steps colder but OEM grade NGK Iridiums.

 

Iridiums and platinum plugs were created for one reason. Maintenance. Especially with the way some engine configurations are and the requirements of removing intake manifolds just to get to the plugs. These were created to last the test of time to lower the maintenance costs.

I'm sure most of you don't remember this because you are young but back in the day spark plug replacement was done at every 30K at the very max.

Copper plugs were the norm. Copper plugs are still your best choice for performance. They make a much fatter spark line that is less prone to blowing out under high cylinder pressure (boost).

The only down fall with copper is that you have to replace them more than a platinum or iridium plug. Platinum and iridium plugs can remain hot under performance applications where a cylinder is getting lean or too rich with not enough timing becoming a glow plug lending to detonation.

For your daily driver, iridium FTW

For your turbo charged or high compression beast, copper FTW.

 

Would it be necessarily 'bad' (or would there be any benefit?) to run copper plugs in a NA engine?

I ask because I read that copper plugs provide a better spark for better compression which means more power. In order to get that same spark from an Iridium or Platinum plug, the gap would need to be larger.

 

Copper plugs have been used in "NA" motors for decades. It has a lot to do with what the engineers designed the car to use with the components of the motor.

 

True. But, I guess what I mean to ask is: will there be any performance gain/loss by putting copper plugs in my stock tC? Or will it just be a null effect?

 

nice post don, i might try some copper plugs sometime.. which one is good for the tc?

 

your not gonna see a performance gain on a N/A car just get OEM