I just picked up a 90 anniversary car which seems to run just fine, but i kindof think there is something goofy with the vacuum with it. On the stock guage, and idle, it pulls about half way between 10 and 20. Shouldnt this pull more towards 20?? Also when im traveling down the highway around 70-75 it says im almost not pulling any vacuum, like only 1 or 2". This doesnt seem normal to me. Could this be part the car maybe having a boost leak problem? Thanks For the help