Are Big three automakers' wind tunnels up to the top speed of cars?

I was reading up on wind tunnels and saw where some firm bragging bout their wind tunnels for NASCAR car testing can get up to 155 mph. (https://www.aerodynwindtunnel.com/about-us)
Well, I thought NASCAR cars could go 200 mph. So my question is, if some American cars (like the new Corvette and present Ford GT) can go 200 mph, why don't they have wind tunnels that can create a 200-mph wind? I don't mean with 1/3rd scale models --I mean accommodating the real chassis with the proposed body? Also why don't they use a more malleable clay that the wind could push around a little and re-shape? I think Toyota must have had something like that on the back window of the Prius Prime which if you look at it has a shallow "dip" down the center" like the roof of a Zagato-bodied Abarth of the '50s. In other word, the wind could reshape it, if they had a more malleable clay. Instead the clay modelers shape it, put it in the tunnel and measure it but the wind doesn't get any say in re-shaping what its flowing over (like the wind does on a sand dune). I am saying I have the impression wind tunnels are not high velocity enough, can't even generate 200 mph yet they are building 200 mph cars. And the clay is too hard to be influenced by the high velocity airflow. Here's a video of BMW i8 in a tunnel
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TECHNOLOGY : BMW i8 DEVELOPMENT l CLAY MODELING & BMW AEROLAB WIND TUNNEL TEST l Clip
but again they are measuring what the sculptors have built beforehand and rolled in, not letting the wind reshape anything. Anybody have an opinion?
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FORGOT THE PRIUS PRIME BACK WINDOW
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