This was my first time trying the 4.3 mile configuration (5 mile track without the hairpin turn, and instead you end up on a longer back straight. My lap timer says the result is about 4.3 miles).
I somehow got a 3:13 on my 2nd lap out just before the track shut down for lunch, and then got rained out. No idea how fast it is, or not, but got a couple of nice 4K videos out of it, and viewsync can play both at the same time (try it out, pretty nice)