Well as you probably aware there are a lot of factors that can affect reaction time and that's why delay boxes are so popular, with them you can adjust one perrameter very accurately.simple.
You can affect reaction time with ballast but it also affects ET logically ballast on the front should slow reaction times somewhat and ballast on the extreme rear may speed them up.
Front Tire size will also significantly change reaction times an I know some racers even play with their front tire pressures to adjust their reaction times.
Equally important is how you stage and at what RPM you leave at you must be very accurate, if you don't pay very close attention to how you stage your wasting your time.
I would like to give some food for thought concerning using a delay box while they can greatly improve your driving (reaction times) the same holds true for everyone else in a box class so the margins are much thinner and almost everyone is capable of cutting good light. While there as some racers who can consistently cut good lights with out a delay box in general there are fewer of them because it takes more practice and experimentation to do so and most people don't want to put in the effort or time.
If your new to the sport I would suggest that you master the techniques required to be a consistent no box racer before you start racing box class as it brutal out there! People regularly lose with .020 or better lights!
