302 heads for 318
Long story short.Heads and cam won't show a huge jump with out the carb but the carb won't show a huge gain without a better exhaust.You have to move more air IN and OUT to get a huge gain.But doing the heads and cam is fine but adding the 4bbl and headers will show up better.Keep in mind the pistons are a big HP killer in the 318.If you put the 2bbl back on try not to over jet it as you want the A/F ratio to be right more than just throwing jets at it.