I use to drag race several different stick cars, you can change the first gear ratio to make the car leave harder without changing the rear gear
IE, we used a early A body NP833 23 spine tranny in my old 340 Duster street and strip stick shift car, the stock first gear ratio in them is 3.09
My current street and strip car I'm building now has the O.D. NP 833 tranny with the same first gear ratio and .64 % over drive, I'm using a 3.55 ratio Dana 60 in that car with a 464 C.I. 440 motor on pump gas, hopefully the O.D. tranny will hold up to a little abuse