Torsion Bars???

Hey forum... Well I am getting ready to do alot of work to my '72 Duster... A question has been haunting me is what size torsion bars should I get?
I will be a running a 360 904 tranny 8 /34 rear with 3.55 gears for a street/strip set up... more street than anything. any suggestions would be greatly appreciated... THANKS

Dan

Mopar or No Car