when I changed the engine in my old clio when it decided it didn't like one of the piston rings anymore I ran it at high rev's, worked the gears and also ran it on high octane fuel for the first 1000 miles so the rings would open and the boars would expand, I did a few local runs on the A1 up and down to just bed it in and make sure I didn't miss anything then took it down the M1, round the M25 and back up the A1 and across to the M180 as its really empty after 11pm so I could really put my foot down (121mph), got away with my first speeding ticket too that night for doing 91mph on the way home once I explained why I was speeding lol