It's the calipers that make the biggest difference, increasing from 300 to 320 discs will only give a 6.7% increase (torque = force x radius). When I did the upgrade for the earlier models I calculated there is 33% more pad area and 133% more piston area.
So I am looking for info on the 4 pot mod to the older Connies. Cost? Parts needed? Thanks
If you're using the stock size discs of 270mm diameter I can supply brackets to suit Nissin 4 piston calipers, I don't have any in stock at the moment though. See link below:
http://gtr1000.yuku.com/topic/3638/4-piston-brake-calipersRegards, Russell