Hello all, i was wondering if i needed to go with one step colder plugs in my r53. The only mods i have are a catback exhaust, k&n typhoon intake and sprint booster. Am i fine with my factory plugs or should i get one step colder plugs? Thanks for your help!

 

last year i had a 15% pulley, cai and exhaust and went a step colder, the plugs fouled and i've been using the oem since. i check it pretty often and it's holding up really well.

 

Run the stock plugs till you get a pulley