BMW N54 Spark Plugs Guide - Best N54 Spark Plugs
4. BMW N54 NGK 97506 2-Step Colder (500-700+whp) If you want one of the most proven BMW spark plugs then look no further. People run these spark plugs on everything from highly modded N54, N55, N63, S55, S63, B58, and more engines. They're actually OEM spark plugs for the N20 inline-4 turbo engine.