Trackdays in general are fairly busy until about 1:30pm where cars start to retire (break down), people start watching instead of participating and others go home early (the same can be said with drag racing at WSID).
Wakefield is a fantastic track to learn on. My lap times went from 1:35sec -> 1:21sec on my first outing and I was barely pushing the car (more so pushing myself to trust the car). I think with some semis-slicks and another 50 laps of practice (my car did close to 90 laps on my first time at Wakefield) that I could be down into the 1:15's