Can someone help decode my transmission nubers and recommend gears?

[camtra]

I'm trying to find out what kind of transmission I have in my 69 Charger. My numbers are as follows: PK3681864 4743 0116

I'm trying to figure out if it's a 3 speed, 4 speed, or what? I'm getting the gears in my rear end changed out and I'm trying to figure out what gears are best. Any recommendation and opinions are welcomed.

Thanks

 

[Greg Ducato]

that trans is a 727 from behind a 1974 400-2bbl, it is a 3 speed automatic with a top gear ratio of 1 to 1. Gear according to how the car will be used, higher numeric ratios for best acceleration, lower numeric ratios for best economy and lowest engine rpm. A 3.23 is a good compromise gear.

 

[camtra]

that trans is a 727 from behind a 1974 400-2bbl, it is a 3 speed automatic with a top gear ratio of 1 to 1. Gear according to how the car will be used, higher numeric ratios for best acceleration, lower numeric ratios for best economy and lowest engine rpm. A 3.23 is a good compromise gear.

Thanks