That is a very small cam. It should work with the stock converter and 3.08 gears. Should also work with stock springs. Just make sure to check the lift the spring can handle. If you are after a good daily driver with decent mpg and power, that is a good cam.
Yes, those heads suck, but will get you going down the road.
You need to run around 15 degrees of timing at idle and 38 at 3500 rpms. Get an adjustable vacuum advance (crane, summit racing) and set the vacuum advance to 12 degrees and use it on the manifold vacuum source.
Tuning is critical. A 450hp engine in bad tune can make as little as 300. A 300hp engine in tune should make 300.