my '64 Custom, I had a choice, from the factory, as part of the 427 package, of a 4.11 or a 3.50. I got the 4.11 but within a couple of months, two other guys and I decided to drive to Florida for the 12 Hours of Sebring. I swapped-in a 3.50. With 8.20-15 tires on the rear we had a cruising speed of 70 at 3K RPM. Overall trip mileage was 11.7 MPG but we ran for long stretches at over 100. The best single tankful gave us 16 MPG. (Your experience might vary!)
With the 3.50 gear and the 8.20 tires, It was easy to shift back into third at 100 and use it to play with other cars--- such as a 409 one time. And then there was a corvette... The car got quite float-y at about 130 due to having spring jacks in the front coils. But even with the nose in the air I could get the speedometer needle to show in the red idiot light over to the far right of the speedo span. I did a little cheat-sheet showing tach reading and speed in fourth, and had it taped to the dash.
|This message has been edited by ectarecordholder on Apr 20, 2017 8:51 PM|