I'm sure that if they cut the length of the intake guide down in the bowl that it would flow even more, but not sure if the heads are finished the way they look or if they do that before
assembly.
they do look massive, but I understand they're $10,000 a pair. If you can get them.
Right now I'm happy with the Bob Walla heads that I bought... Z-12's are awsome though, someday when I get old and retired and have a lot of money hopefully you can buy a complete z12 crate motor to bolt in, then you can find the weak Link in your drivetrain and break some crap! (Not the motor though).