Just thought I'd share my solution to the vacuum connections on bike carbs, didn't want multiple pipes, y pieces and a smoothing vessel.
The steel tube, should provide smoothing as well as connecting the seperate runners.....

Oops better post the pic

Been there done it etc
then dump it
sorry but i could not get it to work
i must say it was not exactley like yours.
4 pipes in a tank 1 out to the dizzy + i tryed one way valves aswell
good luck with what you are trying let us know how you get on
Graham

[Edited on 3/3/08 by jacko]

looks just like mine

seems to work but not been far in it yet

dave