I would hit the track tomm and just run it like you would normally and go about 65% down the straight,let off and coast. Then on the next tank hold it on for a little more down the straight. check your temp every 3 or so laps . 238 is not hot for this motor. If it starts getting really hot fatten the top 1 or so and lean the bottom 1 . then see how it runs from there. It will not just break in and be perfect on 10 tanks .