Miramar Speed Circuit, cart racing 5 minutes of exhilaration for 25 bucks, and worth it. Trouble is, you'll want to do it again.

The above shows a guy spun around, and the guy standig is trying to get everyone sorted out without any one crashing into each other

http://www.miramarspeedcircuit.com/ for all the info, but important to know is that it's one block North of Miramar Rd, closer to interstate 15 than the 805, East of the pyramid and West of Camino Ruiz. Take Cabot from Miramar Rd or Miralani from Camino Ruiz