As to rear axle ratios, the 2.93 was usually a 318/automatic ratio. With the shorter 7.75x14 or 8.25x14 tire, that gave it a particular cruise rpm range which was suitable for the 2bbl carbs those engines came with. But with B/RB cars, with their larger 8.55x14 tires, it was 2.76 with the 2bbl cars in order to use their greater torque for relaxed highway cruise rpms. 440 NYs had 2.76 as standard, too. Usually, everywhere the 2.76 was standard, the 3.23 was optional and vice versa.
I figured that our '66 Newport with 2.76 and 8.55x14 tires would do 28.66mph/1000rpm, for example. The 2.94 was used in Imperials with their taller 9.15x15 tires and heavier weight, possibly as a way to compensate for the taller tires?
300s, being the "Sporty Chrysler", would naturally get 3.23s as standard, with 2.76s optional.
With the factory HP motors, the 3.23s were standard for a couple of reasons. A LOT of those engines were sold to law enforcement entities, where acceleration was important, so to guarantee those customers got what they needed, as standard equipment, it was 3.23s. Plus it got the engine into the meat of the power curve sooner, so all the much better. No worries about highway fuel economy, either, as "getting there fast" was more important to those customers.
To me, relaxed cruising and a 2nd gear which can string out to 90mph at WOT is what I desire. Off-line acceleration should be responsive, not necessarily "rubber smokin'". With that "relaxed cruising" also translating to "increase fuel economy at cruise", too.
Everybody has their own orientations on "cruise rpm", off-idle response, and such.
Enjoy!
CBODY67
