It can be confusing for non-enthusiasts, but the 3L measurement in this news is the blower, not the engine. This is the metric used for positive displacement blowers, in particular, like the Whipple. The engine is still 5.0L.

For a moment I was excited. I'd be a little bit interested to see someone come up with a smaller V8 -- more efficient, but still all the right noises! Still have higher pumping losses compared to fewer cylinders, but might be worth it even still.

You don't have a strong understanding of automotive engine design, do ya?

The engine is still 5.0L. The supercharger is 3.0L. And that is why it makes 810 horsepower.

(Looks sadly at the 1.3L Eaton supercharger on my workbench and feels inadequate)

Point of clarification - that's a 3L supercharger on a 5.0L V8, not a 3.0L V8