Thanks! I have seen those books in like every catalog. But I never knew if they were worth it. A 427 side oiler has been my dream engine ever since I was 14.
I have a old set of 200cc iron eagles in the roughly 11-1 350 in the mustang, with a hydraulic cam its went a best of 7.43 at 91 in the 1/8 mile. They are not the greatest heads out there but are far better than any factory heads