what size torsions for a 69 dart for a little better handling?

i installed a pair of nos .890 (383 Dart) bars in a '69 dart and to be honest i found them to be no different than the stock 340 bars....oozy!My current '69 Dart has nos .920's in it with bilstein shocks and there is a noticeable improvement and i'm sure the shocks help.It has a more modern feel and you can actually push it's limits...a bit!
I like it, but is not nice on rough roads!Problem is it's such a personal thing and what one likes another might not.
As for the bigger 1"...i've never used them.