spark plugs

[sphs2]

Hi, i want to change the plugs in my 89 390se but am confused about what type!, the car is fitted with champion RN7YCC, the plug guides say champion N7YC and the heath book says NGK B7ECS! HELP!!!

[grahamw48]

I think the NGKs are what most are using...certainly had them in my 390.

[GRIFFONMARK]

RPI Engineering's site says 'Use good quality Plugs such as NGK BP6ES, and avoid fancy plugs, as they don't normally last long'. My 350i has used these for 2 years with no probs until yesterday when it refused to fire. I don't think it was the plugs though, it'd be a crappy coincidence if they all packed up together.

[leorest]

NGK here also. Same set for the last seven years! Should I be thinking about replacing them yet?