I had a 65 Olds Delta 88 which had a 425 rocket V-8. It was rated at 360hp but I think that was conservative because it ran like a bat out of hell.
Too heavy to compete with the muscle cars but still fast. I once drag raced a hot rod Chevelle SS396. I beat him for the first hundred yards or so. Mine had posi-traction which helped.
It actually got better mileage than my wife’s 73 Cutlass Supreme with a 350. It did have to have premium tho.
I drove a Gremlin-X for a while in High School. It had been re-painted, but the “X” striping kit was on backorder so it looked like the base model. I had fun with for awhile.
I currently have a 2013 Audi S6 with a 4.0L V8 Twin Turbo and AWD. Audi understates it by a lot at 420hp and 0-60 in 4.6 sec. The car tuners say it is stock 480hp and Car and Driver clocked it at 0-60 in 3.7 sec.