Originally Posted By: raaizin
Wouldnt it fill faster if it didnt fill in the tube, but directly into the tank
Some people do that, and it will fill up the tank slightly faster. However, the refill tube serves an important purpose for toilet performance, which has been explained.
However, a universal fill valve and refill tube isn't necessarily the perfect solution. It's a one size fits all solution that doesn't necessarily account for the size of the bowl, the intake flow rate, or the amount of the flush. The refill tubes tend to be oversized to ensure that they're providing enough water for the bowl even with a high efficiency toilet. With mine I could see that the bowl fill was already at the maximum in less than a half of the time it takes to fill the tank. Mine is 1.28 gallon per flush, so obviously the original refill tube is oversized. So I modified it with an adjustable refill tube (with a pinch mechanism) to time/slow the fill rate to the tank fill time.