2 barrel to 4 barrel?

Might check to see if you'll have a port mismatch with the intake. Honestly, if the car runs good, save your goodies for when you do a rebuild. If the motor is a stock rebuild, you'll need to know a few things like static compression ratio, converter size, gears, etc to spec a cam to go with your intake and carb to see a gain. I guess it all depends on what you intend or are doing with the car?