I Have an 78 305 Qjet Runs Ok .I am Looking to find out 2 things First My carb Has only two vacuum lines hooked to it One comes out at the top passenger side front corner and goes to the distributor. The other comes out of the Driver side and hooks up to a tee then goes to the pcv valve and on to the brake booster All the others are Just capped off. My car gets lousy gas mileage some times if it dosnt start right away cold or warm it floods itself out. Could the fact that none of the vacuum lines are hooked up be the culprit. Any and all help will be appreciated p.s. can the car continue to be driven this way?

Sounds like the dist. is hooked up to manifold vaccum.It will work,but not exactly correct.Sounds like it's hooked to the spot that the choke pulloff is normally hooked. The PCV and brk. booster should not be together.The pcv should be a 3/8" hose at baseplate front of carb. The booster should be at rear baseplate,or possibly the intake manifold vaccum port(where the trans vac. hose is) Is the choke working/sticking? Are there any vaccum canisters on pass. side of carb,if there is ,check that it's hooked up and holds vaccum.There may be 2 or only 1, may be none.Have you checked the timing,tuneup?

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68 z28 ,68 rs 327 ,73 454 vette, 2 goofy kids

I had the timing checked it was fine i just recently did a tune up on it plugs wires air , fuel filters all changed
Perhaps someone has a diagram or scematic they can scan and send me it has a manuel choke no A/C No form of emissions type stuff on it and by the way there arent any canisters at all like i said two vac lines total .....well three one comes out of the carb and hooks to the choke diaphram .
The two that come out of the front base plate are capped off there are no vacuum lines what so ever coming out the back of the carb.there is a place for one right behind and below the one hooked to the choke it is also capped off .And one more up higher on the front also capped off

the one at the front in the middle, it is a 3/8 size port is for the PVC. the other is for the dist. in the front. the one on the back in the middle is for the power brake's. the one on the passenger side top is for the choke pull off on a elc./hotair choke.

use the small on off the front of the base plate for your dist.

to tell if it is ported or timed vaccum, un plug it at idle if you have vaccum it is non-timed. if you have no vaccum at idle but if you rev the motor up and get vaccum it is a timed port.

now ther is a big contravercy over timed, manifold for vaccum advance. i say use manifold. it give's you a better idle and the minit you open the carb up it is gone anyway. and it is back at cruse for better fuel milage. other's say use timed...i do not know why. all car;'s used manifold till EGR system's and such became the norm....if you do not have an EGR or any other emmision's except a PCV i say use manifold.