new Z4's N52 engines - power output

[Smokin]

actually.... isn't 98 RON (Europe) equivalent to 93 AKI (US)?

I believe you're correct. Most every gasoline station lists "93" as the octane of their Premium. "Regular" is 85 to 87 and "midgrade" 89 and it's not calculated the same way as octane in Europe.



While Wikipedia may not be the definitive source for information, they have a nice write up of "octane". US ratings are based on both the RON and MON.
http://en.wikipedia.org/wiki/Octane_rating

 

[konstantinosz4s23i]

hello to everybody!i have the new z4s23i..do yoy know if there is a supercharger kit for this engine??