If this was chuckwalla run by Raceline then it was probably quite a few ITRs. I go to that shop sometimes and ive met a few guys there. So many of them are ITR owners and they all go to track. Of the ones i met i think most of them are just i/h/e with avg 190whp. Planning to go hang out this sunday the 8th when they do buttonwillow.
I went on May 15. Had stock suspensions and intake, header, cat-back bolt-ons. You don't need much to track, tires and suspension is all you need. It's a great track for beginners. Buttonwillow is a little more difficult as there are changes in elevations in some turns.