with 274@50 - first I would dump that 440source dizzy and go with an MSD unit - but if budget demands use it but watch the internals as they have a tendency to destroy themselves after awhile. As far as a curve you will want about a 10 degree curve with all timing in by 1500 - 1800 RPM. The light weight mr gasket springs usually will get you there - if not drill the counter weights to lighten them up. another way is to lock it out and use a start retard function AKA msd starter saver or a digital 6 box