The upper one only has vacuum at part throttle for the vac advance.
Quote:H-- NO,
Thanks guys
It looks like my metering block has been swapped out at some time by some idiot. Mine only has one place for a vacuum port. How much vacuum should be on the correct port at idle? OR is there a part number for the correct metering block that has the 2 ports on it? Is it Ok to run the vacuum line to the base plate if the port on the metering block will not work right?
Unless you want wide open throttle at start up 
Call Chicago Corvette and give them the list number(It is on the back side on the passenger side of the center carb. 
)and buy the correct metering block for your carb DO NOT hook the outboard carb vacume pod lines to the manifold vacume, if you do it will open the outboard carbs up immediately(SP?) as soon as you start it up 
Chicago Corvette bought all of the Holley six pak replacements parts years ago, I hope they can help you still . BTW, use the word Tri Power when asking for parts, not Six Pak This will help you stay under there radar as a rich, well heeled Mopar guy 
No Don't do that as Cab said full throotle while engine running on the out-boards also your doing good asking on here these guys are good just don't get in a hurry and do something you regret also try to find someone in your area with six pack experience to help you out. Even if its just with some phone calls. 