Sorry to disappoint, Stevo. Had a doctor's appt. this morning, fortunately it wasn't the kind where he goes all exploratory with the index finger while the patient sings Moon River.
But, um, yeah. A lot of folks there will run either the Falken Azenis RT-615k (which is the new compound) or the Dunlop Direzza Sport Z1 Star Spec.
In terms of how many you will need for the race, MSR-Houston isn't hard on tires in a lightweight car. If you start the race on 4 new tires you'll likely have those last the entire race, although if you're experiencing heavy wear on one axle you might swap them front-to-back overnight. If you have a new set of tires on the car and a set of 4 spares you will be quite well equipped, any more that that is just wasting money. If you wanted to save a little cash, you could bring just 2 spares and you'd probably be fine. Good luck!
Pat Mulry, TARP Racing #67
Mandatory disclaimer: all opinions expressed are mine alone & not those of 24HOL, its mgmt, sponsors, etc.