Quote:

Are the rectangular heads better than the oval port??



Only if your motor needs more cross section & slower port speed.

The Diamond rectangle port is basically just same as INDY 360-1 rectangle port, except little bigger everywhere.

The Batten rectangle port IS the 360-1 port because, well ICH bought the Batten tooling when they went Bankrupt in late 90's. Only thing they really changed was the intake valve guide boss.