By themselves I doubt you would feel any difference. If you were to add a 4 barrel and intake and cam, lifters, and valve springs then it adds up. Always have the magnefluxed by a good machine shop before putting a lot of money into them.
This^^^ Definitely want to upgrade the carb and add dual exhaust if you haven't already. If you are into it that far a 340 cam and roller timing set is definitely worth doing!