If your running an aftermarket cam, it's usually a good idea to have the heads redone, but I won't harp to much on that, cause I'm not
A set of headers and an aftermarket intake manifold will help it breath better so your cam will actually have air to move in and out. A Quadrajet should flow alright for your application, but just make sure it's adjusted to your application (change after the cam break in period, it should atleast be able to run at 2000+ rpm for 30 min as it is, if you mess around with it now, you could have problems)