Welcome to the board!
Yes, to take advantage of a 4bbl swap the cam needs to change. You can do headers, but honestly, until you're north of 300 HP the gains are negligible. I'd keep the logs for the time being and have a shop run a set of 2.5" duals for you with a balance pipe. The cam you pick is going to be matched against the style of driving you're doing, rear gear ratio and compression ratio (stall rating of the converter is also a factor, but you're not going to need to worry until you get beyond a certain point).
So, what's the intended usage of the car? Current exhaust setup? What's the rear gear ratio? Compression ratio?
If it's all stock then a few of the guys here will know the answers to the last three questions right off the tops of their heads. If gear ration is a question though there is typically a stamped steel tag on the rear axle with the ratio number.
Once we know more of the specifics of the car we can give good advice on parts selection.