Lars997:

check this: http://en.wikipedia.org/wiki/Octane_rating

That has a good example of why you can only roughly convert from RON to AKI. Above, I posted a rough conversion of RON 100 ~ AKI 95.5, but from the table on that page:

Shell V-Power in Italy and Germany 100 88

That's the RON and MON, respectively, for the indicated fuel (I believe that's the fuel RC is using), which gives an AKI of 94, rather than the rough, generic calculation without knowing MON of 95.5