Ok guys

Heres a hypothetical, lets say you have a certain b body that weighs 3860 with a mildly built 440 engine hooked to a 727 transmission with 2500 stall torque converter, and lets say for the sake of argument it has 3:23 gears and it goes 14.0 in 1/4 mile. 28 inch tall tires

What kind of gain in ET will be seen in going to 3:91 gears, same tires?

Mike