DD would you know if the ribbed crank and waterpump pulleys where available?

I think Ive worked it out? Alternator spinning at 2.4 of the crank
SC pulley is 80mm and alternator is 50mm SC should be spinning at
twice its capacity for 9.5-10psi so need 2:1 ratio.
Back of alternator pulley needs to be about 67mm in diameter
to make the 80mm pulley spin at 2:1.
Now to find a way to get a custom made waterpump and crank pulley
for 6 or 7 ribbed belts. I would prefer stepped belts like on belt
driven overhead cam engines but too expensive to make the pulleys
and could be noisy.

As long as you are consistent with where you measure I don't think it will matter.

As for the maths.. hmm, can't help off the top of my head sorry, I would probably have to work it out in a spreadsheet or something. Technology has made me stupid!

Anyone know if the A series cam with ribbed crank, waterpump
and alternator pulleys in South Africa????

Also anyone know who can modify or make some in Victoria?

Im thinking of using 6 rib belts for the crank, waterpump
and alternator while at the back of the alternator to drive
the supercharger stay with 4 ribs like on the stock rib that
comes standard on the supercharger.

At the moment Im trying to work out the diameter of the V pulleys
they come stock with as its quite hard to work out exactly what
the diameter is with a V groove. Any ideas on correct method?

Im using the bottom of the V and got 120mm with the alternator
at 50mm meaning 120/50 = 2.4:1 for the alternator then the
supercharger pulley is 80mm so what would I need if I need the
ratio of the supercharger to spin at 2:1 instead of 2.4:1 ?

Im lost in the calculations specially when adding 500cc to the
mix and the A10 with 75mm bores or 1043cc