I haven't read ths whole thread, but does it look like 2 air boxes on opposite sides of the engine? Possible electric supercharger?
Originally Posted by Boss330
There might be a different part number, doesn't mean it's a totally different design though... They where based on the std. engines.
I guess you can do the exact same thing on Realoem.com with the next gen M3 engine. Plenty of different part numbers that separates it from the engine it is based on.
Bottom line is, those S engines revved like an //M engine is suppose to rev. No N engine was close to 8,000 RPM, let alone 8,250. They were leaps and bounds better than the standard engine. You can tune an N54 to around 400wHP on pump gas now with bolt ons and a tune.