Ideally most including myself would probably want an 8 3/4. However that's not happening in my near future (lack-o-loot). My questions are:
How can I tell what gear ratio I have? From reading previous forum info, my best choice according to my driving for both mileage and responcevness is the 323 or something like that. If I decide to change the gear ratio how hard is it on a 7 1/4? I know once upon a time I've done a swap on a 8 3/4 and it wasn't hard. Thanks, Dale

I believe the options were

2.93
3.23
or
3.55

I temporarily hooked up a tach, and then figured out found out the rpm at 50, easy cruise (in third 1:1 ratio, and minimal torque converter slippage- manual transmission doesn't have to worry about slippage). Then did the math of comparing that rpm to the 2.93,3.23, or 3.55 ratios rpms you'd get.

BTW, mine came out to be 2.93

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Chock both front wheels. Lift ONE rear wheel off the ground; leave the other on the ground. Make a mark on the inboard sidewall of the lifted tire, so you can see it from under the car. Chalk works.

Transmission in Neutral, handbrake released.

Turn the lifted tire through two complete revolutions and watch the rear U-joint. I find it easiest to count U-joint caps. There are four of them per revolution, so each cap facing the ground represents a quarter-turn of the driveshaft. I just count the number of U-joint caps that face the ground over the course of two (open) one (suregrip) tire revolution, then divide by four, thus:

16/4 = 4 = 3.91
14/4 = 3-1/2 = 3.54 or 3.55
13/4 = 3-1/4 = 3.21 or 3.23
12/4 = 3 = 2.93 or 2.94
11/4 = 2-3/4 = 2.71 or 2.76
10/4 = 2-1/2 = 2.45
9/4 = 2-1/4 = 2.26

That covers the range of ratios that were available over the years in the 7-1/4" rear axle.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Dan, I woke up this morning, logged on and saw the light! Thanks for the info, Dale