is it worth installing cam in stock 318?

Your engine is just absolutely perfect for a Hughes Engines whiplash cam. Those cams are ground to work with stock engines. Even works with stock springs. they are ground to sound really choppy, but provide excellent low end torque and raise cylinder pressure for additional power. If i were you, that would be the camshaft I would be looking at HARD.

Here it is: http://www.hughesengines.com/Index/...V2hpcGxhc2ggTXVzY2xlIENhciBDYW1z&partid=25113

There is even a video there so you can hear how it sounds and see the car run that has it.