My 74 2.0 has only one vac line attached to the dizzy.
The one on the bottom is on. The top line point has nothing on it. Why!?!

Where does the hose start from that goes to the top?

Haynes diag shows black hose coming from " intake air distributor ".

The car runs great BTW. Just need to set the CO content with a sniffer.

Thanks all

http://www.pelicanparts.com/914/technical_...4_20FI_diag.htm

Props to Dave the great, it's his diagram. Mine isn't identical to the pic, so I can't give you an exact description, but that link should help you.

Its for the vacuum advance which the 74 throttle body don't have a port for. You can drill and install a port for it and gain alittle hp between 2000-2500 rpms.

Geoff

the factory had a hose on there that was just laying on top of the engine, not connected to anything.

so, i assume, you're fine
Andy

Sounds like that highly technical german enginering process of placing a golf tee in the end of the loose hose.

No need as there is no air in the hose that is only connected to the dizzy.