The top running cars at almost any track are not likely to be illegal, at least not knowingly. Anyone can have too much left side weight, or be light, too low, or forget to register tires in their inventory, and in that case they would be illegal but not cheating.
Cheating to me is deliberate, outright. Bolting a 4 barrell on a car where the rule says clearly only 2 barrels, is deliberate. Being outside the rule at tech is a mistake most times, and usually not deliberate. Cheaters for the most part try not to finish where they'll get caught, winning heats, and top three in features. Sometimes tracks do a random check as well and that can keep everyone in line.
The top 3 at Sunst are legal, for sure. They have been tore down completely, what they did or do to their engines etc is in the rule book. Every team has the opportunity to buy a new car, and take it to the max, the top cars, and a few others at Sunset have done that.
As for the Sunday race, it was a good show.
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