L series
There are 2 diameters of clutch on the L series
228mm for intercooled versions
215mm for non intercooled versions
A standard OE 228mm clutch is good for about 250ftlb on a good day.
A standard OE 215mm clutch is good for about 200ftlb on a good day.
Perkins Prima
There is one diameter of clutch available 215mm which is essentially the same part as the non intercooled L series