I used to get at least 5-6 days if not more on Pilot Sports (granted PS2s) or RE050s (non-runflat). My bet is you were pushing them awfully hard - if you're going to drive THAT hard (based on times), I'd suggest a proper track tire, inconvenient as it is to own multiple wheels, cart them around, change them there, etc etc... Maybe you can luck out and have a friend with a trailer bring them for you?
