This subpart specifies gaseous emission test procedures for Otto-cycle and diesel heavy-duty engines, and particulate emission test procedures for diesel heavy-duty engines, as follows:
(a) For model years 1990 through 2003, manufacturers must use the test procedures specified in § 86.1305-90.
(b) For model years 2004 through 2009, manufacturers may use the test procedures specified in § 86.1305-2004 or § 86.1305-2010. For any EPA testing before the 2010 model year, EPA will use the manufacturer's selected procedures for mapping engines, generating duty cycles, and applying cycle-validation criteria. For any other parameters, EPA may conduct testing using either of the specified procedures.
(c) For model years 2010 and later, manufacturers must use the test procedures specified in § 86.1305-2010.
(d) As allowed under subpart A of this part, manufacturers may use carryover data from previous model years to demonstrate compliance with emission standards, without regard to the provisions of this section.