mk2 carb vacum pipe

[sellers]

theres a vacume pipe on my driver that goes from something next to the dizzy to the brake servo pipe that comes from the manifold,

whats the little vacume pipe do??

[rickoty]

It supplies vacuum to the servo to make it work, - gives brake assistance.

[sellers]

yeah thats the pipe that goes from the manifold to the servo, but theres a smaller pipe that T's off it and goes to something next to the dizzy??

[Haribo!]

im sure its something to do with timing and how carb works wiith the engine, the pierburg needs it for something, i had a weber and the timing had to be different so now i have a pierburg again i have to block off that vacume pipe until the timing is done again or els my engine wont drop below 2300 revs.... i dont know exactly what it does tho