Honestly, you would be better off with complete PI head kits with PI intake. This will gain more than just cams on the non PI heads.
Unless you want to do both head/cam/intake upgrade, then get bare heads with values, and build them to match your cam specs.
But in your shoes PI heads/intake would be the better upgrade than just cams. IMO. And I wouldn't think you need a tune, but I'm not sure. But with cams you need one regardless.