40 CFR § 1068.235 - Exempting nonroad engines/equipment used solely for competition.
The following provisions apply for nonroad engines/equipment, but not for motor vehicles or for stationary applications:
(a) New nonroad engines/equipment you produce that are used solely for competition are excluded from emission standards. We may exempt (rather than exclude) new nonroad engines/equipment you produce that you intend to be used solely for competition, where we determine that such engines/equipment are unlikely to be used contrary to your intent. See the standard-setting parts for specific provisions where applicable. Note that the definitions in the standard-setting part may deem uncertified engines/equipment to be new upon importation.
(b) If you modify any nonroad engines/equipment after they have been placed into service in the United States so they will be used solely for competition, they are exempt without request. This exemption applies only to the prohibitions in § 1068.101(b)(1) and (2) and are valid only as long as the engine/equipment is used solely for competition. You may not use the provisions of this paragraph (b) to circumvent the requirements that apply to the sale of new competition engines under the standard-setting part.
(c) If you modify any nonroad engines/equipment under paragraph (b) of this section, you must destroy the original emission labels. If you loan, lease, sell, or give any of these engines/equipment to someone else, you must tell the new owner (or operator, if applicable) in writing that they may be used only for competition.