A process for the preparation of saturated hydrocarbon base oils is provided, comprising oligomerization of a feed mixture that has an average carbon number in the range of 14 to 18 to produce an oligomer product comprising dimers, trimers, and higher oligomers, where the dimer has a branching proximity (BP) of 20 or greater, isomerization of at least the dimer portion, and hydrogenation of the isomerized product. The dimer portion is separated from the oligomer product, and a saturated hydrocarbon base oil is obtained comprising greater than 90% dimers having an average carbon number in the range of from 29 to 36, and the dimer portion having a weight average molecular weight in the range of 422 to 510, where the dimers have an average Branching Index (BI) in a range of 22 to 26 and an average paraffin branching proximity (BP) in a range of from 18 to 26.