Okay its gotten to that point where the influx of newcomers to the platform is rapidly rising and there are several common questions that get asked repeatedly and this will focus on a few maintenance items. For the sanity of the veterans to the platform, it is nice to have threads like these to reference. This post will hopefully answer some of those questions and I will update this as much as possible as information evolves. Lets get to it: Spark Plugs (Thanks to @[email protected] for this info) BOSCH ZGR6STE2Identical to OE and cheaperNGK 95770 (ILZKBR7B8DG)1 Step Colder (FBO+)Autolite XP 56821.5 Steps Colder (FBO+)NGK 93026 (DILKAR8A8)2 Steps Colder (700hp+)NGK 97506 (SILZKBR8D8S)2 Steps Colder Injectors There have been several revisions to the injectors over the years with Index 12 being the most recent at the time of writing and seemingly the most reliable. There are many places to get these injectors for a significant discount over OE sources, which I will leave up to you to locate. It is important for various reason to ensure all six injectors are replaced at the same time with the same type. You can mix and match Index 11 and 12 injectors with the correct coding, however you may experience bank variances. One additional bit of information is in regards to injectors is an extended warranty for certain build dates. See below if you qualify for reimbursement: Coils Anyone purchasing new OE coils should wind up getting the new design with the metal housing from Eldor which seem to be a solid choice. There have been a few performance oriented coils such as the Okada Plasma Direct, however its been said that there are better ways to spend that money. There are also many people running the N55 coils by Delphi. Eldor #12138657273 Delphi GN10571 Upgraded Coils There are currently two upgraded coil offerings: BimmerLife TuningSmart CoilPrecision RaceworksDumb Coil If any of this information is out of date, incomplete or incorrect please notify me and I will revise it.