Not sure what to do

318 cu in..........is always going to be 318 cu in. And it is never going to feel like 418 cu in.......

I agree with above. A four barrel intake is probably going to give you the best bang for the buck. Easy to do, minimal amount of work, minor engine disassembly..

If you wanted a large HP increase, better to get a bigger engine.

Use the Performer intake [ not the RPM ] & a 600 Edel AFB carb. Some will come come after this post & recommend the 650 AVS carb. For this performance level, it will NOT add anything over the AFB except to lighten your wallet...