With that many runs, especially if they are all close together, the tires might get hot and greasy. Bring a pump up pressure sprayer with water in it to cool the tires down if they start to get too hot. Also bring a tire gauge as the tire pressure will climb because of the heat, so you can drop them back down if they get higher than you want. Might want to raise the hood between runs to help cool off underhood temps, if there is time. On other cars I've autocrossed I would always shut them off between runs (they were all naturally aspirated), but I noticed with the ST that oil temps stay lower if I leave the car on between runs, especially on a hot day with a co-driver.