The 3.73s will help you get off the line better and keep the engine in the power band more - I'd guess you'd pick up a couple 10ths in the 1320 if you use this (multiplied torque) to move the car and not to spin the tires.
3.73s are a poor choice for NA 1320. You'll be shifting into 4th before the end of the traps putting your car out of it's power band. At most you'll gain a couple of tenths.