Voluntary submission of additional data.

(a) The manufacturer may optionally submit data in addition to the data required by the Administrator. (b) Additional fuel economy data may be submitted by the manufacturer for any vehicle configuration which is to be tested as required in § 600.507 or for which fuel economy data were previously submitted under paragraph (c) of this section. (c) Within a base level, additional fuel economy data may be submitted by the manufacturer for any vehicle configuration which is not required to be tested by § 600.507. [91 FR 7774, Feb. 18, 2026]