(a) A separate vehicle configuration shall be determined by each combination of the following parameters:
(1) Exhaust system (engine):
(i) Mufflers;
(ii) expansion chambers;
(iii) spark arrestors; and
(iv) other exhaust system components.
(2) Air induction system (engine):
(i) Intake muffler;
(ii) intake ducting; and
(iii) air cleaner element.
(3) Vehicle drive train:
(i) Chain; and
(ii) shaft.
(4) Transmission gear ratio:
(i) Standard transmission; and
(ii) automatic transmission.
(5) Cooling system configuration:
(i) Natural air cooled;
(ii) liquid cooled; and
(iii) forced air cooled.
(6) Category parameters listed in § 205.157-2.
(b) [Reserved]