The 'Sport' models were just a cosmetic exercise anyway, but as with most styling exercises people tend to credit them with being a more 'special' type! I was once informed by the owner of a 'sport' 3 litre model that the (face-lifted) rear end and the little front spoiler made it more aerodynamic . . .
Most of the hype surrounding these models comes from magazine road tests and books such as that by Mick Walker, where we are informed that the 'Sport' models have an LSD - quite true, but they never tell their readers that the other models for most markets also had an LSD. I believe that Japan and Singapore were among the few markets where an LSD was not a 'standard option.'
Anway - as most models were fitted with a Torsen differential, which is an infinitely variable device, the 25% label is pretty meaningless, but it keeps some people happy - such as those sad folk who want to imagine that they can hang the rear end on bends, or perform silly acts such as doughnuts etc!
