You've seen them around for years, you may have considered running them, you may even have them on your car right now. But do exhaust cutouts really serve any purpose beyond rattling the drums out of passersby's ears? Well, proponents have always claimed they make your car faster, but on this episode of Engine Masters, presented by AMSOIL, we see how they stack up against a full exhaust and a header extension behind our heavy-breathing 598-cubic-inch Big Block Chevy. We run them in multiple positions as well as both open and corked to see just what effect they have on power, no matter how you want to run them.