70 dart 470 ci drag car build.

Roger that. I do have the bug that when something does need replacement. "Why not go hotter?" Lol.

The B1s are nice. Plenty beefy for some impressive flow porting. 15+ years ago Edelbrock, Indy, Stealth ect couldn't touch them. But as you are aware. They closed the performance gap.
In the context of what you are saying the B1BS was never ahead of the -1 Indy unported especially. They aren't a bad head but even 'all-out' they can't touch a similar prepped -1. Even though B1 original is a better head you'd rarely find one run better than a good -1 build.