Flipper Coil FL-15411 Orange
It is not recommended that you "tinker" with the balance of flipper power supplied by the original flipper coils. But if you must tempt fate, here is a list of coil numbers and their relative strength going from weakest to strongest:
FL-11753 - Used with short flippers and close shots
FL-11722 - Used for close shots near drop targets
FL-11630 - The standard, most commonly used coil
FL-15411 - Used for long playfield shots
FL-11629 - Used for long shots and high ramps