www.dodo-upgrades.nl

I've checked it again and it is BKR6E - 11 indeed. The only difference is that they are made in France. Right now on third cylinder I've put a used NGK, made in Japan. However I am considering a new set for install asap.
About the oil leakage in the intake maybe its from the mistake i made by putting too much oil. The engine simply regulates its level by throwing it out by the least resistance points(oil vapor etc). From what i saw i can not say that there was a problem inside the engine that caused it to throw oil. I will continue to investigate the problem because i am considering more tunning to the powertrain. And don't want to do it on an engine that has a problem (hope not).
Thanks for the replies, i will continue to inform you on the project and hopefully help others with similar issues!

Cheers!
Edit:
In respect to the above wich model of NGK spark plugs would you sugest i should buy? The same as before, iridiums or other type?

archyman wrote:In respect to the above wich model of NGK spark plugs would you sugest i should buy? The same as before, iridiums or other type?

Iridium of course, part number NGK BKR6EIX-11, they will last the double kilometres.
But because iridium are pricey it is fine to buy regular ones too, BKR6E-11.

all these years I have been using iridium ngk sparks. I get them through e-bay for 35euros. Still I don't keep them more than 35.000km. They aren't the long life version and everytime i get them out they don't seem very hard used. Still, I don't feel very safe keeping them more. Maybe my idea.

saxophonias wrote:They aren't the long life version and everytime i get them out they don't seem very hard used.

I am hearing first time such thing. NGK doesn't refer something for Iridium spark plugs with short and long life, does she?
Please feel free to correct me.
If they don't have rounded or worn electrode tips they can hold up to 60,000 Kilometres.