I think your guessing...!
The Clean Air Act dates back to the 60's (actually 1955 if you count the Air Pollution Control Act which preceded the CAA), with the last major revision being the amendments in 1990. It established air quality goals and tasked the EPA with enforcing compliance, specifically from what is termed "mobile sources of pollution", AKA motor vehicles. Catalytic converters exist because of this law, as do the complex engine management systems now used in all modern vehicles on U.S. roads. The EPA did not invent those systems or devices, they simply mandated a level of emissions output and the vehicle manufacturers developed the tech needed to meet those requirements.
Guessing?
You can run a VIN number car on a track all you want. No one is banning anything on a track as long as it still has it's OEM CATs, etc. If it has a VIN it is subject to the regulations. You can run street cars on tracks but you can't run off-road vehicles on the street.The Clean Air Act dates back to the 60's (actually 1955 if you count the Air Pollution Control Act which preceded the CAA), with the last major revision being the amendments in 1990. It established air quality goals and tasked the EPA with enforcing compliance, specifically from what is termed "mobile sources of pollution", AKA motor vehicles. Catalytic converters exist because of this law, as do the complex engine management systems now used in all modern vehicles on U.S. roads. The EPA did not invent those systems or devices, they simply mandated a level of emissions output and the vehicle manufacturers developed the tech needed to meet those requirements.
I have not seen any actual wording within the legislation specifically banning the use of a street legal vehicle in motorsports, or modifying a vehicle that is never used on a public highway even if it started out as a street legal vehicle (it is an excruciatingly long document, so I doubt anyone, including the EPA, has read every word of it). The problem is, it doesn't specifically permit those things either, and the EPA being an ultra liberal bureaucracy prompted by a liberal administration has "interpreted" this law to include all vehicles produced for use on public highways, regardless of how the vehicle ends up being used. The intent of the CAA was pretty obviously to stop people from defeating the emission controls on vehicles still used on the roads, but the wording doesn't limit it to just that. That's why the RPM act is so important. It specifically exempts off road only vehicles from compliance with the CAA. Without that clarification, or any clearly defined limits of the application of the law, the EPA "could" if it wanted to, start hanging out at race tracks and handing out fines to all the racers as they were loading up their racecars onto trailers for modifying the emission systems of those racecars. That's not likely to happen, but as the CAA stands now, it would be within the EPA's power to do that. The only way to avoid breaking that law if you want to modify a car for racing, under the EPA's interpretation of it, is to drive a vehicle built before the Pollution Control Act of 1965, so it wouldn't have any emissions devices on it to tamper with, or build a car yourself from the ground up, and never title or register it for street use. Anything else is subject to EPA enforcement.
Now if you drive a car on the street, and chose modify it in a way the alters the emissions systems, well then you're on your own.
Colorado has them at on ramps to highways randomly.
How much?
