Hmm maybe ratio the size to length size:length

None unless you get water on the top and have a fork of three things down.

Just use a random number generator to randomly open certain EWALLs with portals behind them. Well... you can also have it lead to separate pips, but that would take longer.

i've got a way.. it takes some work and a bit of tweaking..
(do all of this in pause mode)
1. build the cups and everything else
2. build the pipe in a kind of arch motion where the split is facing straight down
3. split the pipe but make all ends the same length
4. open the three ends
(unpause)
5. when the pipe starts to build itself make sure all three pipes meet in the split's middle AT THE SAME TIME.
6. if they meet at the same time you should be good... otherwise, keep going
(pause)
7. as long as opening the pipe ends was the last thing you did in TPT,for windows, press "Ctrl + z" to go back to when you cut the pipes ends. (Mac users i don't know what to press)
8. whichever of the 3 pipe ends was the slowest, slightly shorten that pipe.
9 . repeat steps 5-8 until they meet at the middle at the same time.

Thanks for reading this and i hope it helps
P.S. i have done this, for some reason i cannot log on to the powder toy so i cannot upload my version..sorry

P.P.S. i got my TPT to log in. if you want to see a very simplistic 3-way pipe. search "tri pipe" and find mine hope this clears up any confusion you may have

@Tazman12345 (View Post)
This could help a lot of people, good job!