Rig set up settings.

I went to a training weekend at the Weymouth Portland National Sailing Academy. The two instructors recommend these settings when rigging your boat:

From masthead to transom should be 6540 to 6550 when you have rig tension measured at 24 on  a Loos gauge. This is about 300 lbs of tension.

The spreader length should be 860mm (measured to the centre of the shroud wires) and deflection 165 - 175 mm.

The mast should be stepped with 3 holes showing in the step to the rear of the mast.

If you have these settings then they said dont mess with it. If you aren't getting the results you want then better to think about your boat handling and race craft.