The stockers are 3.07s and with the 0.50 6th, a lot of owners were never happy with the overall GenI/II gearing. 3.55s and 3.73s are a common upgrade for driveability. It's not really that bad stock with the V10 twist as it'll idle along in 4th gear, but it's an easy mod. The 3.07s also allowed them to set 0-60 times without shifting too...
@ttyymmnn Sputnik was launched in 1957 and the space race was on. I wonder how much of the radical change in styling was due to jets and how much due to rockets.
The Jetsons first aired in 1962, so I would assume that the concept art would have been created around 1961. The Jetson's car with tailfins and bubble canopy seems to fit with Detroit's concept cars of the late 50s. This makes me think more space-age than jet-age.