+fireamx, that article is dated last modified 1996? It references testing of cars like a 1978? Surely these statements can be taken with the premis the information is correct but is it prudent for the MB112? Also, the engine was designed for and originally used in the european fuel markets so I would think the octane ratings are skewered there some given the differences in fuel design and regulation?

I have been using the premium octane here, it is set up locally 87, 89, and 93. Since I hear from some they use the regular I might try the mid grade here and see how the motor reacts. Every once in a while, I will hook up the OBDII tool to see if any problems come up (as well as listen for any noise in the motor).