indy or edlbrock

As far as I've been able to tell a 400 based Victor with a Dominator flange is not out yet. You'll have to go with the Indy single plane 4500 400-14-3. It is an excellent manifold for high rpm racing. We've used the 400-14-3 to get 787hp @ 7200 rpm from a 451 on 91 octane with Edelbrock Performer RPM 440 heads.

But, consider, many builders have reported better power with a 4150 based manifold and a 4500 adapter to the Dominator carburetor.