We plan on testing a set of Air Flow Research's 220cc SBC heads on a 400 cubic inch small-block in the foreseeable future and we hope to make over 550 on 91 octane.

 More like "as close to 600 as possible." The heads flow and impressive 304 cfm at .550 lift, 312 cfm at .600 and 318 cfm at .650, and with a cam spec'd from Tony Mamo we feel confident we'll make some good numbers. We also plan on spraying it with nitrous at the track once it's in the car. Keep reading CHP to follow the build.