Who is this clown?
Note that the ZR1 ran on an oval, which will prevent it from reaching its TRUE Vmax. The Koenigsegg CCR had a similar issue when it did its top speed run at the Nardo Ring. 241mph is nothing to sneeze at, but it could've gone faster had it been on a completely straight road, a la the Veyron.
But when it's done in a proper location, this happens: https://www.youtube.com/watch?v=UEYuouTFB4I
207mph and change, Vbox verified. And if you look closely, you'll see that for a fraction of a second, it hit 208. This is in-line with Chevy's claim that the ZR1 was capable of 210mph during testing.
And then there's this: https://www.youtube.com/watch?v=d3cLWsNAJKM
202.7mph in a 1.5mile run(looks like the Mojave Magnum event). He went so fast that he would've been shut down for rule violations had it not been his last run of the day anyway. And while I can't verify that the car was stock, all evidence points to that being the case. Stock ZR1s run 180+ in events like the Texas Mile, so adding another half-mile to the run could net 200+, provided there's no headwind. If it was modified, it would've gone much faster than that. In the video, they mention another run they did that was "only" 189mph, which is actually kinda slow for a ZR1 running 1.5 miles; there are guys who have done 189 in just one mile in stock ZRs. So there's no reason to believe the car was modded.