Are you asking how fast people on here have driven their Buicks? I know some of us have been faster then others would dare in a Buick. A few threads about this before.
I've done 145 in my car once. (Not here on the autobahn, car is not here in Germany) I kept it there for a minute. That was without the Bilsteins. It was getting floaty and a little scary. I'm sure if I tried again, I'd feel better about it. I thought about bringing the car over here for Autobahning but I would want the car to be in a lot better shape. Brakes, lower, 16s.
I know its not a Buick but I shagged 200 mph on my '04 ZX10R Ninja before my kahones ran out. The bike was still pulling in 5th gear when I shut it down. It only has a few minor bolt-ons.
Just so you know... I'm an English teacher that knows British English. The verb "to shag" can be translated as the American English verb "to f uck" So, please be careful using that. Not really imporant I just laughed when I read that.