Actually there were 10 different chassis combos in the top 10. The top TC3 has a aftermarket carbon fiber top deck/bottom chassis and has a shorter wheel base. Enough differences to consider it a different model.
Many of the people at our track are running fans in VTA. I've run a TC4 with a large heat sink and no fan and have qualified near the top in the past. Difference in motor temps at our track with/without a fan are usually around 10 degrees. Regardless, if you are getting a motor without a fan over 150 degrees at our track, your car isn't working well.