The car is a 78 Euro 911 with all emission devices removed, ie no air pump and related plumbing and if it ever had a cat she doesn't have one now.
rebuilt the engine and while hooking up all the various bits of the intake system I discovered the top (verticle) vacuum hose is block by a screw. What is this device used for and should I hook it back up?
Here is the device
The upper most hose is the one that is blocked.
Here is a photo of the engine on a hoist moving from the stand to the dolly.
Thanks for the help
Osidak
78 911sc Targa