NASCAR engines use 110 octane race gas which is leaded. If the octane were only 101, it would be unleaded race gas. Several attempts have been made to make these engines survive on unleaded fuel. No luck so far. Detonation or pre-ignition are not the problem, valve seat recession is the problem.
But the larger point is: why is NASCAR so technically backward? Why aren’t fuel injection, computerized engine management, traction control, ABS brakes, data collection systems, and many other technical advancements approved for use?
Too costly? Not likely, since NASCAR is awash in television money. To technical? Not likely, since most top teams have factory engineers guiding their crew chiefs.
Loss of power? Most likely: the loss of power and control of the sanctioning body over clever engineers.
NASCAR would like to propagate the myth that its all about the drivers, and driving ability, which is just patent nonsense. A well trained chimpanzee could be taught to drive a properly set up race car. Repeat after me: its not racing, its a business, its not racing, its a business, its not…