Why are 318's low HP and torque?

Hmmm. I see. So a little of everything and I could really wake up my little 318 huh? Well I am building a mostly stock 318 right now. I currently have a street master four barrel intake manifold with a 650 Carter, stock exhaust manifolds... What else would be easy to do without breaking the bank to wake up my 318? Do you guys have pics of your 318 setups to give me some ideas?

http://www.summitracing.com/parts/SUM-6900/