[MrPbody]

No "production" 389s had forged cranks. The 425A (389 SD) engines had a forging. VERY rare... Most were "ArmaSteel". That is, WWII armor, recycled into cast steel. Good cranks. With the 3" mains (389/400), under 750 HP, a forging is not needed. We've done some 455s with as much as 900 horsepower with the nodular iron crank. The block becomes the weak link over 650.
You will need good forged rods. We use Eagle, almost exclusively. Best for the money.
Word to the wise. Go to some of the Pontiac-specific sites (performanceyears.com, boyleworks.com (muscle cars) and classicalpontiac.com) and ask their opinion of Rock and Roll "Engineering" . Let the buyer beware.
A 440 Pontiac is a .060" over 428. It has a 4" stroke. IMO, the MOST effective race combination from factory parts.
Edelbrock and Kaufmann Racing make excellent heads for the Injun. The E-heads require a bit more exhaust system (round ports versus "D" ports). The KRE heads seem to be the better for a streeter at reasonable levels of tune. The E-head can be ported to flow more in the long run.
For racers, there's a new head coming (still in development, but well on the way) called "Tiger", sold by allpontiacs.com. Once they get their valve train issues resolved, it will change the face of GM racing, bringing Pontiac back to its rightful place at the table, smack in between SBC and BBC.
KRE also has introduced a "high port" version of a round port head. It is in the performance range with the Edelbrock, and responds to modifications very well.
A new intake is also out now, called "Tomahawk". It's a large, open-plenum that will "fit" under a T/A shaker scoop. Initial reports place it on a par with Torker (1) for power production.
The most important investment you can make for your Pontiac today, is buying Jim Hand's book "How to Build Max-performance Pontiac V8s", by SA Designs. It is a CURRENT study of the Injun engine. It dispels some myths and tells you real world changes to make to make it tougher and faster. It's target audience is the street engine crowd, not the all-out racer.