340 whiplash vs. voodoo vs. thumper

Welcome to the site Aaron.

With a 4spd and the 4.10 gear you have plenty of options. There are several grinds from all three that can work for you. The limiting factor may come down to the rocker gear you're using and whether the heads have ever been worked for a larger spring then stock? Also, what is your intended use, street only, street/strip or mainly strip with limited street use?