If I made a small step change from 3.23 to 3.55 and GOT PLENTY HAPPY I can guess a bigger change up to 3.55 will get more happiness.

I could get 100-110 miles on little bit less than 4K RPMs ( in D ). 27" tires.

but for all around use I woulnd't go higher than 3.55

With a Charger born in Chrysler assembly plant in Valencia, Venezuela