New Mexico Statutes Chapter 66. Motor Vehicles § 66-12-10. Muffling devices

The exhaust of every internal combustion engine used on any motorboat shall be effectively muffled by equipment so constructed and used as to muffle the noise of the exhaust in a reasonable manner. This may include but is not limited to such devices as mufflers, exhaust restricters and water-injected exhaust headers. The use of cut-outs or non-muffled headers is prohibited except for motorboats competing in a regatta or boat race approved as provided in Section 66-2-15 NMSA 1978 and for such motorboats while on trial runs during a period not to exceed forty-eight hours immediately preceding the regatta or race and for such motorboats while competing in official trials for speed records during a period not to exceed forty-eight hours immediately following the regatta or race.