This is a very good point. A car with the right gears transmission and setup such as yours would only need a true 450 horsepower to approach the 11s and when you talk about 600 horse you're nearly doubling what the factory components were designed to work with. now combine that with the fact that most of them are 50 years old, you will have to address pretty much everything in the drivetrain. That being said it is very doable.
