4 bbl carb question

[Dodgerdallas]

Got a 66 318 poly and I replaced the 2 bbl carb with a 4 bbl and an adapter to the 2 bbl stock intake,problem is when i start it it revs very high and then drifts immediatly down and dies,you can gun it before it dies and it goes way back up then back down.Ive got all new gaskets of course but doesnt this sound like its sucking alot of air? any ideas?

[A383Wing]

gasket not sealing? PCV nipple with no hose? Open passage on back or front of carb?

[Dodgerdallas]

Stayed some carb cleaner around the base and it revved up a little everytime,can't understand why all gaskets are new,maybe thicker?

[polywideblock]

had this problem , if the adapter plate has slots instead of holes for different bolt patterns. they leak through the slot you need to "glue" the gasket around edge so its sealed on outside of slot. doesn't sound right but i hope you get what I'm trying to get across. if someone can put it better feel free

[A383Wing]

get the correct gasket instead of glue if that is what's wrong

[polywideblock]

actually meant gasket goop not glue                      wish i could draw on these things ,it was a "lynx" 4 barrel adapter and to make it fit different bolt patterns it had slots .when bolted to 2 barrel poly manifold there was a hole at each corner from the unused slot when it was used with gasket for stock carb

[Dodgerdallas]

It's a Holley 600,Do u mean seal the manifold gasket? Thinking about just making a better one the one that came w the Trans Dapt adapter seems thin and flimsy

[polywideblock]

ifits got the slots look under carb mounting and see if you can see end of slot poking out from where adaptor meets manifold e.g. its not the carb to adaptor you need to check its the adaptor to manifold

[Dodgerdallas]

Ill check it when I get home today thanks