I'm playing with a set of the open chamber heads Edelbrock heads on my Duster right now only because I got them for a "real good" deal. I ported them and went a 9.74 and 9.73@135 mph first day out.

1970 Duster
Edelbrock headed 408
5.984@112.52
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time