Anyone know if the size of vacuum lines used in plumming the boost controller and other things matters? I bought some new silicone stuff to replace my old stuff and it will fit over the nipples with some mild force, but is about have the I.D. as the old. I'd say it's about 1/8" I.D. vice the old looks just over 3/16" I.D.. Thanks, 88 T2.

 

You generally use hose a hair smaller than the nipple they are meant to go on. THat way they fit properly without blowing off, and the appropriate amount of airflow can still happen. There is very little actual flow happening over these fairly short distances, though, so it is not critical.