..from the Motor Oil Bible.
VI + Flashpoint(F)+ 20(HT/HS)+ 2(TBN)- Pour point(F)- 3(NOAK)= Oil Rating (higher = better)
There are ratings for mostly SL/SJ oils on the site to spring 2003 in the appendix.
If this has been discussed before I couldn't find it in a search. Opinions and comments? Advantage to have a higher VI#?