Depends on how you built your engine. If it's a looser build (like most race engines...why do you think we run 20w-50?), then the break in is a lot shorter and redline is only a couple hours away. I have 500 miles on my 390HP, and it sees redlineonce in a while. The engine will tell you if you're pushing it too hard. If it's a tight build, then you'll need to give it a couple thousand miles before really running it hard.