Yeah fronts vented with magic holes , rears normal but vented .
6 pot version have 322mm but their much lighter 2 seater convertible with same 4 pot derv engine has 344mm .
344mm belong on a heavier family estate .
Film strength of oil HTHS .
As with oil not everything would be as it seems and higher the oil film strength the greater the anti wear .
It's caused me to raise an eyebrow regarding the racing Ester marketed oils.