Edelbrock part throttle surge help

I'm thinking I need stiffer springs in the metering piston. I'm.pretty sure It's running lean, if i spray fuel with a spray bottle into the carb at light throttle it smooths out and runs fine. As soon as I stop it starts to stumble and miss. I'm gonna get a timing light on it and double check my initial.
AJ, don't you think.It would run rich with this 268 cam? I thought it made less vacuum than a stock cam? If it makes less vacuum wouldn't the springs act stiffer so to speak?