Torsion bar compliment to 340 XHD Spring

Kind of an interesting question that got me thinking. I had upgraded my rear leaf springs to Espo 6 leaf (340 XHD) which have a spring rate of 130 lb. I understand that Torsion bars should compliment the leaf springs, so on a car such as a V8 Duster, what is the correct compliment torsion bar up front. I already bought the PST 1.03” bars which have a rate of 230 lb in., but figured I would ask the question, it could benefit others going this route, or I could be off in my selection of parts myself. I know the consensus is that 1” minimum bars really should have come from the factory and no one has been sorry they upgraded their torsion bars either. How does one determine how much spring rate they need for just an average well mannered car that is just a street car, and not a full fledged drag or auto cross car?