My 83 euro 500 sec is running NKG BP5ES & runs fine also.
Oem spec plug on engine label is Bosch W7D or Beru 14 7D
Found cross ref equiv to BP6ES.
Bosch sites are confusing
Say BP6ES is equiv to WR7DC
Same bosch site matches WR8DC which should be a cooler plug
with the much hotter BP5ES.
This seems to suggest BP5 is cooler than BP6 which it is not.
Alo this site lists slightly hotter plugs for hi mileage engines or lots of idle & short trip stop * go driving.
That makes sense to help prevent fouling.
Thats why I went a slight hotter.
I have had no problems with the car but wondering if this could affect the smog??/
Also reinforces that you have to run correct FA ratio....
About Spark Plugs
Now I'm getting lost...just want the best for my beast.
