Wake up a 1968 318...

It's a 318 1 barrel? If you just want a little more gitty up, I'd look at a fresh valve job, new timing chain, dual exhaust (make sure your heat riser flap is not froze shut in the exhaust manifold), recurve the distributor, and you could add the 4 bbl /intake. I would stay away from the cam in the van, unless you hope to spend a lot of time over 3500 rpm's.