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Hello my name is***** will toss a couple things your way for you to check. Number one. The hesitaion or stall on acceleration could be due to the vacuum advance. Make sure your base timing is set correctly. Base timing is the timing set with the vacuum advance hose disconnected. Next plug the vacuum advance hose on and the engine idle should stay the same. You see there are two types of vacuum for carbureted cars they were manifold vacuum and ported vacuum. Manifold vacuum is vacuum from the manifold when the throttle is closed. Ported vacuum is vacuum when the throttle is open. Distributors used ported vacuum to advance ignition timing when the throttle is open. This gave the car that snap off the line thus taking away that bog or stall feeling. Number two. Carburetors had what was called an accelerator pump. When you first open the throttle a small stream of rarw fuel would spray down the throat of the carburetor. This was important because without it the car would bog and sometimes stall. This is very east to check. With the engine OFF not running look down the throat of the carburetor and open the throttle by hand if you see a small stream of gas it works. If you see nothing it is bad. Good luck and I hope this was a help
FYI Ported vacuum ports were always located on the carburetor and identified as little vacuum port nipples above the throttle plate. with the use of a vacuum gauge put the gauge on an open port with the engine running at idle. with the throttle closed vacuum gauge should read zero. when you open the and throttle and the vacuum gauges responds you have found a ported vacuum port.
Thank you, ***** ***** happy to help and thank you for choosing JA.