On a side note, the vast majority of cams that Indy Cylinder Head supplies / recommends are split pattern. Whilst these guys may not be the easiest to speak to over the phone, I'd bet they've used some dyno time trying different types of cams and maybe found whats best for Indy heads. Sorta tells me something
Hi Tig , maybe you can ask Indy the reason for going split with their heads next time you speak to them , my bet is they don't know.
