3999289
Best 454 block other than 4 bolt #289 and #512 which are too expensive to buy usually.
I use 2 bolt #289 blocks for 750+ HP 496 bracket engines without issues.
Suggest ARP main studs and line hone for drag race use.
I still have about 6 complete 454 1970s engines saved back just for 496 engines.
About any MARK 4 454 block will work good.