How far would the Environmental Protection Agency go to cut greenhouse emissions on vehicles? According to SEMA, the trade association that represents the automobile aftermarket industry, the EPA is working to ban the conversion of street cars into competition-focused racing vehicles.


In a statement released late last night, SEMA accused the EPA of hiding this proposed goal in a dense, esoteric, 629-page document in the Federal Register published last summer.

SEMA, which has opposed the rules since last year, insists this proposed regulation “would impact all vehicle types, including the sports cars, sedans and hatchbacks commonly converted strictly for use at the track. While the Clean Air Act prohibits certain modifications to motor vehicles, it is clear that vehicles built or modified for racing, and not used on the streets, are not the ‘motor vehicles’ that Congress intended to regulate.”


We are still going through the massive document, but this seems to be the portion that has raised the ire of SEMA and, potentially, enthusiasts everywhere:

Certified motor vehicles and motor vehicle engines and their emission control devices must remain in their certified configuration even if they are used solely for competition or if they become non-road vehicles or engines; anyone modifying a certified motor vehicle or motor vehicle engine for any reason is subject to the tampering and defeat device prohibitions of paragraph (a)(3) of this section and 42 U.S.C.

From that language, it seems as though any tampering with emissions controls would be outlawed, even if the vehicle isn’t a street-legal one used only for competition.

At the same time, additional language in the gigantic, complex Federal Register document implies competitive vehicles would be exempted under the regulations:


Competition engines/equipment: (i) For uncertified engines/equipment that are excluded or exempted as new engines/equipment from any requirements of this chapter because they are to be used solely for competition, you may not use any of them in a manner that is inconsistent with use solely for competition.

Update: And this text, too:



EPA is proposing to add a clarification that the exemption from the tampering prohibition for competition purposes does not apply to heavy-duty highway vehicles. This aligns with the statutory provisions for the racing exemption.

So there are some odd contradictions at work here. What’s going on, exactly?

We are still trying to figure out what all of this means. EPA officials have not yet responded to an email from Jalopnik seeking clarification on the intent of the proposed rule, whether the agency has studied its effects on the racing and aftermarket industries, or what the penalties could be if someone is found to be in violation.

(UPDATE: The EPA has responded with comments, which you can find in this updated story.)

SEMA also said they sought to clarify the rule with the EPA, only to learn the agency “indicated that the regulation would prohibit conversion of vehicles into race cars and make the sale of certain emissions-related parts for use on converted vehicles illegal.”



As Automotive News points out, traditionally cars used only for racing are not held to the same emissions standards as stock vehicles, even if they were converted from stock vehicles.

SEMA added this in their statement:

“This proposed regulation represents overreaching by the agency, runs contrary to the law and defies decades of racing activity where EPA has acknowledged and allowed conversion of vehicles,” said SEMA President and CEO Chris Kersting. “Congress did not intend the original Clean Air Act to extend to vehicles modified for racing and has re-enforced that intent on more than one occasion.”

More on this as we get it.


Photo credit Raphael Orlove/Jalopnik

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