[F87source]

Originally Posted by ericlr1225

Feeling nice to find this thread and thanks for the info. It may solve my current problem. Funny part is I'm under a custom tuning process of Cary Jordan Team right now. LOL. They insisted 0.022'' gap new spark plugs must be changed first, then ask them to start tuning process.

Yeah, you never gap down plugs when it is not necessary, you only gap down if you are misfiring due to the spark being blown out. Because the key to spark plug gap is as big as possible without blowing out, this way you promote better combustion and avoid rough idling and misfires.

There is no such thing as a one size fits all gap, so I hate the idea of just following an arbitrary size, you must do what works best for your car.