Q-Jet Usage on a 340

The thing you may have to watch out for is linkage and how the choke works as in electric choke or hot air or...........
Edelbrock offers a 795 cfm unit with the correct linkage I think. It also comes with a thick gasket. If you have an EGR manifold, double check clearance there. Although I think it not a problem, I have not been there yet.

Other manifolds that would work besides stock iron intakes would be the Edelbrock Performer, Weiand Action plus and MoPars single plane M-1.

Noted performance of the Q-jet seems a hair behind the T-Q. But this is only from what I have read in the rags. Taken with a grain of salt.