So I'm a few thousand k off of replacing the spark plugs. Right now, my car is basically stock (other than K&N Intake and one-ball exhaust). I want to do a pulley and maybe a couple more engine mods, but most likely not until next spring. My question is, is the any benefit to running colder plugs in my motor now? Can it harm anything? I was looking at purchasing the JCW plugs.

 

Plugs or Injectors? im confused becuase u mentioned JCW Pugs, which i nvr new they sell =O

 

If you run cooler sparkplugs in a stock motor, you might loose a bit mpg, or they may get fowled/dirty faster, as they will never get hot enough to burn of residue....
IMO wait till you do the pulley, then get the JCW plugs...they are one step cooler than stock S plugs.
When you install plugs, always use a tourque wrench, and install them in a cool head.
In mini's they can loosen, and get shoot out, and you need $$ stuff done to fix them.