Carb issue Autolite and Holley

[1965TbirdMan]

Ok so it has been awhile since ive been on the Army has been keeping me pretty busy. But I have a new 390 in my car and brakes are fixed so thanks for the advice to pull the booster off and spray the brackets to allow the pedal to come back on its own. Although I realized i wish I was not 6 foot 3 while crawling on the floor of the car. Anyways new issue! I had a rebuilt 4100 and i put it on the car and it was leaking which might just be a seal but that isnt the issue. I cannot get the back 2 barrels to work. I believe i have all the necessary linkage to make it work i have the back rod and plastic piece but when I put the lever that is to push down the secondary throttle down it starts to bind so i feel like im doing it wrong or missing a piece and i cant see it in the shop manual.

So then I had an old Holley of ford truck and put it on other than rigging the electric choke to work after a few stalls i realize that i dont have my car still seems sluggish like when i punch it from a dead stop or while driving still doesnt feel like the Holley is getting the back to barrels. Looks like its a model number 80457-2 1562. It looks like the back to barrels are controlled by vacuum which could be an issue because not sure what to put the hose to get it the necessary vacuum.

So does anyone have any ideas on how to make my car have the get up and go it should? I know it is heavy but the engine should still rev more when and if those back two barrels get some gas. Thanks

[KULTULZ]

Both carburetors secondaries operate from engine vacuum which is sourced internally in the carb(s). Both use secondary diaphragms. They (secondary diaphragm) usually do not come with an overhaul kit but must be sourced separately.

Additionally, the cut-in rate for the secondaries is controlled by a spring and these springs are available in different tensions to fine tune secondary opening.

[1965TbirdMan]

Well I think i got it figured out however the carb seems to leaking around the back bowls. Either from underneath or where the back action is that rotates the back butterflies. Both the autolite and holley did this. Also the car seems to load up too. Car got really hot maybe the thermostat takes along time to open but it got really hot and when i would slow down at a stop sign the car would die out. However after the second stall i it ran fine the rest of the way home so maybe the thermostat opened up? the gauge works it says the needle was between the e and m but on return trip it was in between the t and e. I wasnt getting into throttle as much but anyways any suggestions on how to fix this?

[KULTULZ]

Well...

You will first have to establish if overheating and why. Then a carb kit should fix either carb. The engine condition of tune has to be established also.