is it worth installing cam in stock 318?

Well, I was lucky enough to get the car in factory setup with everything still in the car all the way to working A/C and reserve tire still in the trunk. I guess its just for cruising when I finished the body and paint more than performance, because lets be honest. A 318 without turbo isnt gonna be anything impressive so if I would one day want pure performance, I would try to get a big block or at least the 340 engine with 4 speed stick that the guy I bought it from have as well. I just find the car too soft when its idling or on throttle. It sounds very healthy as it was meant to sound I guess, but I like to hear some more of those 5,2 liters, thats all.

With other words, I just want it to sound more "muscle".