Forged pistons for a 350 is a custom order $$$ In the long run it's easier to build a 400 with plenty piston choices.
This is pretty much fact.
Best forged piston value would be if you could find an NOS, or at least a good used set of TRW L2339F030 forged pistons. I found an NOS set a few years back, Never used 'em. Don't know if my engine guy still has 'em or not. Also have a set that are still in a 350 shortblock that came in a '69 Tempest drag car I bought. It got wet in a flood. So, I don't know if the pistons are still good or not.
I suppose it would be worth the time to inquire on all the Pontiac forums & FB pages, to see if you can locate some.
Unless you just insist on going with a 350, the difference in price of new forged pistons could just about pay for a decent 400 core block & crank.
As I've said on several Pontiac sites, the cheapest cast piston option I see is to use 318 Mopar pistons, They're a lot cheaper & have a taller pin height. Will need to have the rod pin holes honed out for the .984 Mopar pins, but will require less machine work on the block, which should more than pay for the pin fitting.
How good are the current cast pistons in a 350. I have no idea. This 350HO engine was built with 357P cast pistons & made 330hp. But, that don't tell you how long the cast pistons would last.
