the rule of thumb seems to be 500 or 1000 miles, but some newer cars will state a certain break in period...but in the same way, some cars come with no break in. im pretty sure that the new Z06 has no break in, as the engine has already had a given number of hours of run time...

1000 miles will be tough for me...we dont go very far when we do leave the house. i dont think that ive put 1000 miles on a single one of my cars in the last year.