Does anyone know what the split is between front and rear drive eg, 40f/60r?

I believe it's 50:50 for all cars except ones with electronic centre diff, where it is naturally ~33:67 front:rear (epicyclic diff unit) but the adjustable diff can vary lock up to the point where its effectively locked to give 50:50... thus you could argue its variable from 67:33 to 50:50. :)