My '62 came with a 3.70 posi gear and 4 speed. I swapped out the '68 327 engine and installed a '63 409. Those 3.70 didn't last long. I didn't like them at all. Even for normal, casual driving, the motor ran too high in rpm's. I had a 3.36 rear from my '57 Chevy and installed them. Just love that ratio. An all around perfect ratio for me and my driving. I cruise around 45-50 mph at about 2200 rpm's. Engine runs at about 180-185 temp. all day long. Very seldom go on the interstates. My '71 GTO has a stock 3.55 gear with TH400 trans. I like that ratio for that particular car. It makes things come alive a little bit better, but this car does see some interstate travelling at times, although I try to limit it, and you can hear and feel the motor working at about 2800-3000 rpm's. I'm not totally happy about that, but it's a trade off for me. Engine will run warmer at those rpm's. I drive this car like I do my '62 for the most part. I like 45 mph but will go to 50 if someone gets behind me. I'm never in any rush. Guess it comes down to, what your intentions are with the car, Carmine.
