There is something to that philosophy of breaking it in like you intend on driving it. I knew a kid whose Dad owned a Pontiac dealership. Every other year he got a brand new car of his choice. One year a 63 Grand Prix 421 tripower, two years later a 65 GTO tripower (that was actually a 421, not a 389) Anyway, he was out racing the night he picked them up and always had the fastest car around, and attributed it to breaking them in hard.

Don