innovations in racing that were sorta cheating included these, that I hadn't learned of until now

 Crew chief Chad Knaus was dinged for rules infractions on more than a dozen occasions. 

His craftiest workaround was rigging the track bar adjuster so that rotating the jackscrew caused the rear window of Junior Johnson’s No. 48 Chevy Monte Carlo to rise outward, diverting air from the rear spoiler and maximizing top speed during qualifying for the 2006 Daytona 500. 

Knaus was suspended for four races and fined $25,000. While Knaus watched on TV, Johnson won the race anyway.

 In 1970 the rules said you could not jack the rear of a Corvette hood up to dump heat. It did not say anything about 6 inch hood pins. At speed aerodynamics would lift the back of the hood to the limit of the pins and the heat would just roil out. They changed the rule for the next year.

https://www.hagerty.com/media/motorsports/top-20-racing-cheats-if-you-aint-cheatin-you-aint-tryin