The basic cfm size of a Q jet is not causing this.
Stumbling on inital acceleration is a function of basic ignition system condition, ignition timing set up
Carb set up. The Q jet is fully adjustable. Start by looking at the ignition system condition and setup.
if the plugs are now fouled, replace.
Is the engine to body ground wire installed? (engine to firewall) This is often left off of recent re-installs
and is a common source of pesky misfire, and easy to correct.
Make sure the brace is on your starter motor too.