Hi All, W108 69' 280s

So all of the sudden Im having fuel delivery issues. Everything was just fine last week with smooth response.
Car starts right up and idles fine but when I go to step on it, it stumbles like its not getting fuel. I cant get it to accelerate really without stumbling and flooring the pedal, even then it chokes. Almost like vapor lock or something

I have a new fuel tank filter, new tank cap, half tank of gas, a few new fuel lines (going to the carb from the pump and the return line from the carb). I haven’t touched anything other than that.
One thing I thought of is that the new lines I used are barely bigger than the original ones. Would that create an issue with the fuel pump trying too hard? I havent had a problem before with this set up as it has been this way for a few weeks.

Would the moisture in the air screw up the carburetion? It wasn’t doing this until the rain started yesterday which happened to be the first day I drove it since I changed brakes.

Im stumped and frustrated

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1969 w108 280s