Which of the lines- white, red or yellow, do I tap into to install the boost gauge?
Dwight

 

White, Red or Yellow? What lines are these?

Are you talking vaccum lines or power lines?

 

I assume vacumn linees produce vacum and others produce boost-which ones?

 

Mind telling us what year c70 this is?

 

If this is a 1998 c70. You should have a vaccum tree located where your throttle body is. If you take that throttle body cover off you will see the vaccum tree. There should be some unused ports just run the line to one of these ports.