Really if you want to push past parts availability of a engine that was never meant to handle 1000 HP, something is gonna snap. You can build a 385 to go much further than an FE just by design, for an FE you would need a custom billet true 4bolt block with splayed caps and thicker deck. Aluminum billet 7005 aluminum rods, billet forged custom pistons lightened with TI pins. And top it off with a custom billet cromo crank. Then you add the SOHC stuff with monster triple springs and titanium retainers, spring seats, keepers and valves. After all that fill the block and you could get to play with the big boys. Hemi, 385 and 572 Chevys are top dog due to the fact that parts are available to compete at that level.