Budget 318 Build

The smaller stock cam will keep the DCR up and help you. The big problem is when someone goes with big head chambers on a starts-with-low-compression 318 and puts in a big cam, and 'blaaaaaaah' off of the line.

I'll tell the "jokes-on-me" story again: Way long ago, I put a 300 duration cam in a 4 cylinder race engine with 7.6 stock CR; DCR was in the LOW 5 range! If you wanted to get on it, it had to be revved to 3800 RPM to get any torque! It was a race engine and could rev to 8k all day long, so it sorta worked with that narrow 2:1 RPM torque band, but it would have a better race car with a smaller cam, and more DCR.

Looking back over your thread, with no new cam, I suspect the headers are gonna be you biggest improvement. The heads will not give you much more with the stock cam, but you'll be ready later.