If you want to see the crazyest inline stuff on the planet, Bonneville is the place to be.
I've only been to speedweek, not World Finals or any of the other events there (not for lack of trying).
I've seen a Deuce Roadster, with a Turbocharged, 320+CID, 12 port GMC, on Nitro, as well as a Hilborn injected "stock" headed GMC (purportedly build by Ed Roth) in a streamliner, not to mention the various flathead inline engines (Packard 6 comes to mind) with custom heads (billet).
I run an inline 4 there, maybe not what you are looking for, but plenty of those there too.
Old Indy engines, the occasional Offenhauser, and the requisite large displacement Keith Black V8s with the largest superchargers on the planet screwed on.
It's the best place to be, but I'm biased.