nice photo of the Triumph with a sprung rear hub… looks like the head has four fins, that would be a early 650…properly tuned it could beat most any car..
I’ll bet the last one was a NASCAR “Stock” single 4 barrel. Also the 250 hp FI was based on the 230 hp 283 engine an actually the most rare other than the NASCAR. They were available with a Powerglide and I actually saw one on tv during one of the auction shows. Not in a Corvette.