I'd love to be able to find out who did the breathing as they can do mine!
...a good start would be the chaps who do the GT3 cars

A V8 usually starts to come into its prime between 7,000 - 10,000 miles.
However, as other have said, there is a lot of debate about the best way to break-in an engine and I don't think it is an exact science (unless you have the budget and resources of an F1 team

)