At the risk of looking like a Hans Stuck fanatic, which I am not particularly, here is a little bit about the guy from his website-
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Heritage
Hans-Joachim's father Hans Stuck
Hans-Joachim Stuck's father, Hans Stuck (1900-1978), was a very successful racing driver and hill-climb specialist. During his 40-year career, he scored 411 wins and runner-up finishes, including seven Grands Prix victories. He set numerous land, water and hill-climb speed records and built the famous AFM race car along with engineer Alex von Falkenhausen. In recognition of his many victories in hill-climb races he was called the "King of the Hills". He raced until he was 62 years old, and won his final German hill-climb championship at age 60 (in a BMW 700). Hans' father was also an accomplished alpine ski instructor and expert golfer.
Here, Hans remembers his father...
"My dad was a good friend to me. He gave me the talent to become a racing driver and he helped me a lot. He was not only a successful racer, he was a good and fair sportsman. He gave me a lot of the things that helped me in my career."
Ferdinand and Johannes Stuck
"I remember all the events, and even up to today, there was never any person that told me a bad story about my dad. This is something I admire very much because in this long career he had, not to have made any enemies is pretty difficult."
"It was exciting for him to see me enter racing, and how much had changed in those 40 years. Now I'm getting older, I can feel how he felt. In my first race, I didn't even have a firesuit on. I went out in normal shoes and shirt, no seat belts, no gloves. It makes me wonder what we're going to talk about 20 years from now, where motorsport goes next, what level it will reach."
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So to answer drive4fun's question, yes, it appears he is the son of the Hans Stuck who raced alongside Nuvlolari.
The only thing I really know about Hans J. Stuck, (Jr), is that when he was driving for BMW in the Speed Vision World Challenge GT series, I think it was 2003, he was being held up by Mike McCann in a Viper Competition Coupe, as they raced at Lagnua Seca in California. Now Mike is a great driver, but not in the same class as Stuck, having far less experience. So Stuck was "stuck" behind McCann, who was busy trying to make his Viper "as wide as possible", driving a defensive line, trying not to let Stuck pass. Stuck wasn't having any of it, and began literally ramming his BMW into the back end of McCann's Viper, repeatedly banging into McCann's bumper, in a blatant effort to get McCann out of the way. The in car video tape showed the hard hits from behind. It was unbelievable to me, to see such blatant aggression. Looked like they were playing soccer! So there is always this element in motorsport, where on the one hand we set rules of engagement, but on the other hand, a real winner will bend those rules as neccessary to win. Drivers not having this killer instinct are 2nd, 3rd place, etc. Anyone else see it the way it appears to me?