Before we get the official response, here's the short and quick answer. USAC D2 cars are Badger/MARA legal (assuming they are D2 legal...) Badger/MARA cars, specifically engines, are NOT D2 legal IF they are built to the full limit of the rules. Not everyone running Badger or MARA is running an engine that takes full advantage of the rules, so there are participants who could be legal at a D2 race, but there have historically been some Badger folk who've been turned away from Thunder events.

With specific regards to the Kankakee race as a "cross over" race, last year, USAC D2 regular Cale Coons won the race and Abby Hohlbein finished top 10. Page Perrine and Michael Magic were also competitive enough to make the A feature.

Basically, when the D2 guys do well against Badger/MARA competition, they like to crow about being down 100 hp, but when they don't do well, the are quick to point out that the Badger engine formula give them an unfair advantage. It's like any dirt race, horsepower isn't always the deciding factor. Track conditions, set up, and driver skill have A LOT to do with winning.