None.
Florida Statutes
§ 316.272. Exhaust systems, prevention of noise
(1) Every motor vehicle shall at all times be equipped with an exhaust system in good working order and in constant operation, including muffler, manifold pipe, and tailpiping to prevent excessive or unusual noise. In no event shall an exhaust system allow noise at a level which exceeds a maximum decibel level to be established by regulation of the Department of Environmental Protection as provided in s. 403.061(11) in cooperation with the Department of Highway Safety and Motor Vehicles. No person shall use a muffler cutout, bypass or similar device upon a vehicle on a highway.
(2) The engine and power mechanism of every motor vehicle shall be so equipped and adjusted as to prevent the escape of excessive fumes or smoke.
(3) A violation of this section is a noncriminal traffic infraction, punishable as a nonmoving violation as provided in chapter 318.
§ 316.293 Motor Vehicle Noise
(2) Operating noise limits.-- No person shall operate or be permitted to operate a vehicle at any time or under any condition of roadway grade, load, acceleration, or deceleration in such a manner as to generate a sound level in excess of the following limit for the category of motor vehicle and applicable speed limit at a distance of 50 feet from the center of the lane of travel under measurement procedures established under subsection (3).
(a) For motorcycles other than motor-driven cycles: Before January 1, 1979 – Speed Limit 35 mph or less: 82 dBA. Speed Limit over 35 mph: 86 dBA. On or after January 1, 1979 – Speed Limit 35 mph or less: 78 dBA. Speed Limit over 35 mph: 82 mph.
(b) For any motor vehicle with a GVWR or GCWR of 10,000 pounds or more: On or after January 1, 1979 – Speed Limit 35 mph or less: 86 dBA. Speed Limit over 35 mph: 90 mph.
(c) For motor-driven cycles and any other motor vehicle not included in paragraph (a) or paragraph (b): Before January 1, 1979 – Speed Limit 35 mph or less: 76 dBA. Speed Limit over 35 mph: 82 dBA. On or after January 1, 1979 – Speed Limit 35 mph or less: 72 dBA.
Speed Limit over 35 mph: 79 mph.
(3) Measurement procedures. --The measurement procedures for determining compliance with this section shall be established by regulation of the Department of Environmental Protection as provided in s. 403.415(9), in cooperation with the department. Such regulations shall include the selection of measurement sites and measurement procedures and shall take into consideration accepted scientific and professional methods for the measurement of vehicular sound levels. The measurement procedures may include adjustment factors to be applied to the noise limit for measurement distances of other than 50 feet from the center of the lane of travel.
(4) Applicability. --This section applies to the total noise from a vehicle and shall not be construed as limiting or precluding the enforcement of any other provisions of this chapter relating to motor vehicle mufflers for noise control.
(5) Noise abatement equipment modifications. –
(a) No person shall modify the exhaust system of a motor vehicle or any other noise-abatement device of a motor vehicle operated or to be operated upon the highways of this state in such a manner that the noise emitted by the motor vehicle is above that emitted by the vehicle as originally manufactured.
(b) No person shall operate a motor vehicle upon the highways of the state with an exhaust system or noise-abatement device so modified.
(6) Exempt vehicles. --The following are exempt from the operation of this act:
(a) Emergency vehicles operating as specified in s. 316.072(5)(a).
(b) Any motor vehicle engaged in a professional or amateur sanctioned, competitive sports event for which admission or entry fee is charged, or practice or time trials for such event.
(c) Any motor vehicle engaged in a manufacturer's engineering, design, or equipment test.
(d) Construction or agricultural equipment either on a job site or traveling on the highways.
(7) Violations.--A violation of this section is a noncriminal traffic infraction, punishable as a nonmoving violation as provided in chapter 318.
Antique
Available for vehicles manufactured after 1945 that are at least 30 years old and equipped with an engine that is at least 30 years old.
Custom
Available for modified motor vehicles manufactured after 1948 that are at least 25 years old that have been altered from the manufacturer's original design or have a body constructed from non-original materials. The vehicle must meet state equipment and safety requirements that were in effect in this state as a condition of sale in the year listed as the model year on the certificate of title. Custom vehicles may only be used for exhibition and not for general transportation.
Horseless Carriage
Available for vehicles weighing 5,000 pounds or less that were manufactured in 1945 or earlier.
Street Rod
Available for modified vehicles manufactured before 1949. The vehicle must meet state equipment and safety requirements that were in effect in this state as a condition of sale in the year listed as the model year on the certificate of title. Street rods may only be used for exhibition and not for general transportation.
FORMER MILITARY VEHICLE
Available for a vehicle, including a trailer, regardless of the vehicle’s size, weight, or year of manufacture, that was manufactured for use in any country’s military forces and is maintained to represent its military design and markings accurately. A former military vehicle that is used only in exhibitions, parades, or public display is exempt from the requirement to display a license plate or registration insignia if the exemption is necessary to maintain the vehicle’s accurate military markings. However, the license plate and registration certificate issued under this section must be carried within the vehicle and available for inspection by any law enforcement officer.
YOM
Vehicles registered as "Antique" or "Horseless Carriage" that were manufactured in 1974 or earlier may display YOM plates with DMV approval.