Originally Posted by
botters
to be honest mate with most of the primaries being welded to each other on that manifold then i would say it will keep on warping regardless of what you do to it
From the photo, it looks like the primaries are welded 3+3, that should be sufficient to protect against warping provided the flange is a suitable thickness.
I certainly wouldnt want individual flanges. Plus the fact the pipes turn downwards on exiting the head, this should also allow for some expansion and contraction during use without putting too much pressure on the flange.