Why are 318's low HP and torque?

If I want to guestimate a potential HP and TQ for my build could someone tell me where I can input my data?

I have a performer intake manifold, 650 Carter AVS carburetor, headman headers drag style and a stock bottom end. Not sure if I'm going to port the heads yet...

I'll put it all in my desktop dyno if you put your combo all in one post rather than me having to backtrack to piece it together.