Trying to figure out what spark plugs I should purchase for my 03 G35 Sedan 6MT, stillen catback exhaust, stillen intake, Z tube, and 5/16 MD spacer, my odometer reads about 60K with stock plugs in it still? I do alot of city driving in Phoenix, but wanna put the best plugs in. Got any reccomendations??

 

NGK iridium or platinum if you want to go cheaper.

 

If you live in PHX and drive the car hard then you might want to consider 1 step colder plugs. As hot as it is here, it can only help.

I run NGK iridium. Platinum are the stock.