Help locate dist. vac .source

I am putting a Q-Jet on a 1971Pont. 455(auto. trans). Q-Jet is from 1978 Buick (stick trans).Carb has large vac. opng for Power Brake & Trans modulator on back (firewall side). Front of carb (Radiator side) has1 large nipple (aprox 1/4")@ lower left on base section, 1 medium nipple (aprox. 1/8") just right of center; also on base sect., and 1 small(aprox 1/16")at lower right side of carb's mid section. There is also a nipple located above the fuel inlet and is aprox. 1/4" dia. and is angled toward the front driver side(I presume this is for charcoal canister?).

I need a vac. source for the dist. vac advance. I want to run direct to carb source and not thru any emission vac. valving. Can anyone identify these outlets or suggest a net site where I can get this info.


Thanks!
Hank

What carb did you have before? Its hard to tell because the vacuum advance canisters were different over the years. Early ones were really stiff and were designed to use manifold vacuum, later ones are light and designed to use ported vacuum.

You can figure out which one you have by sucking on the vac advance with your mouth. If you can move it easily, its the later and needs ported. If you suck really hard and it only moves a little, its stiff and needs manifold vac.

With the Q-jet on and running, pull caps off those ports one by one and put your finger over them. If there is strong vacuum present at idle, its manifold vacuum. If there is little or no vacuum present, but some appears when you open the throttle a little, its ported.

What engine was in the 1978 Buick? You might be better off re-doing your current carb, since the chances that the later Q-jet will be tuned properly for your 455 are slim to nill. Auto vs. Stick, early emissions vs. late, long stroke vs. short stroke... it will be fine if you plan a full teardown and recalibrate a few times, but don't expect a bolt-on.