Looking for a little more power out of a 318

little money- Eddy preformer
more money-Airgap........but, with the air gap you need to upgrade other things, like heads and carb.

Just to clarify for Cole;

The RPM and Air-Gap RPM will perform the same except in warm up times in cold weather driving. There port sizes are 340/360 sized. This is where the extra money in upgrades are. Purchase 340/360 heads or port out the 318 heads.
Otherwise, your good.