3.91s in my 340 now!

I also have a 72 340 Duster that originally had 3.23s and have swapped to 3.91s. Although my 340 is now 422” and I run a 4 speed. In my opinion 3.91 and a 4 speed are a match made in heaven for a street car.
Man, do I wish I had a 4 speed tranny! 3,500 RPM around 60 mph is a little steep, but I would never go back to the 3.23s. It's not a daily driver and I won't be driving all over the place for car shows... a couple times a year I might be making an hour to an hour and a half drive. Thanks for sharing!