More than likely I will just use the heads that are on there now. That LD4B intake is a good manifold correct? If I was to change the cam, would I have to change the springs etc.. on the heads? Thanks
Yes, very good intake manifold. I have used it myself. It'll make power to 6K no problem and then some.
What ever cam you select, purchase new springs that match it. Nearly ever cam manufacturer has matching springs for there cams. You can see there listings on there on line catolog. You should (IMO) change the retainers to standard retainers over your stock one because the factory used "rotors" Instead of standard retainers. Rotors rotate the valves. Get the retainers in the same degree as stock.
As noted a new timing chain is a excellent part to purchase as well as inexpensive. I'd also ad a timing chain tentioner to boot. Also a cheap and very effective part to ad on.
I myself would not bother with Magnum manifolds. If exhaust manifolds are a must have, see my man above selling them. He does nice work. Otherwise, the right exhaust manifold could be a pain in the *** to find, then clean. Treblig Will set you right up with a done part, ready to rock and roll.
Use a cam with 8-10 degrees more exhaust for manifolds, 6-8 for headers which will make a noticable amount of power over manifolds.