I just recently completed my engine swap, 305 to 350, the problem is I have a vaccum line that I have no idea where it goes. It t-s off of the vaccum line for the HVAC system where it goes to the vaccum port on the rear of the plenium. It's about 4 feet long and has another T on it. I can't figure out what it's suppose to go to but its quite long and could reach just about anywhere in the engine bay. So basically I have 2 vaccum connections that I don't know where they go any ideas? I'll try to get some pic's up tommorrow... I'm open to any ideas if you think you might know where it goes.. thanks!

 

Cruise control vacuum supply perhaps?
If you are standing on the passenger side there should be 3 vacuum ports (2 on a MAF car i believe, feel free to correct me ) First one from left to right is for MAP sensor, second one is for Fuel pressure regulator, and the third is for Cruise control... I think... 80% sure

 

 

So the cruise vac t-'s off of the hvac vac supply? That was my first thought as well but I can't figure out where the missing port is.. can't find any on the servo or underneath.. Well thanks for the suggestion I'll have to look at it again and see what I can find..