Round ports are much easier to deal with when making headers & intake manifolds.
Square ports are a pain to make runners for.

This guys paid big bucks to have runners made for his intake ports. post #111 & newer.
http://www.theturboforums.com/threads/353498-Aussie-t51r-feed-202ci-holden-6/page5 $1800 for just the runners.

MBHD

12 port SDS EFI