dual quad small blocks?

Exactly. Place an LA 340/360 intake gasket on one of those Offenhauser dual quad manifolds and you'll see why they cannot be bolted to the 340/360 head and actually seal. The SB 340/360 671 Blower kits used a modified dual quad Offy with welded up port areas. The welding added material and thus allowed them to enlarge the port to 340 size. A dual carbureter non tunnel ram intake manifold was never made for the 340/360 head. You can currently get an Indy Mod Man. But as a dual quad manifold its not a good street intake- but it looks great.

Not true, you had to spec it through Offenhauser.