Equipping your car with a custom exhaust system can give you the performance you want from your vehicle. However, you have to ensure your customizations still comply with NH exhaust laws. In the state of NH, the laws concerning exhaust emissions and noise are specific in some areas but vague in others. To ensure that your custom exhaust system doesn’t violate any laws, it’s important to know what the restrictions are. At Lou’s Custom Exhaust, we’ll ensure you get the performance you want from your vehicle while staying within the law.
In this blog, we’re taking a closer look at the NH exhaust laws and how they affect the design of a custom exhaust system.
Noise Limitations
To prevent excessive noise, all vehicles in NH must have a working muffler. While some states specify a decibel level engine noise cannot exceed—usually between 80 and 95 decibels—NH law does not list one. It’s up to each county or city to determine what counts as “excessive or unusual noise.” In the interest of preventing excessive or unusual noise, the state prohibits muffler cutouts, bypasses, and similar devices.
Emissions Levels
The purpose of an exhaust system is to control the fumes that exit your car and are released into the atmosphere. Once again, NH does not specify the precise limits of allowable exhaust. The law only specifies that an exhaust system must not allow “the escape of excessive fumes, smoke, flame, gas, oil, or fuel residue.” NH requires an emissions test as part of the yearly inspection for all vehicles manufactured after 1996.
Design Limitations
To ensure noise and emissions levels stay within the allowed limits, the law places restrictions on the designs of exhaust systems. For example, it prohibits straight-pipe exhausts. This type of design without baffles is prohibited because it does not meet the definition of a muffler. Fines for violating this portion of the law start at $100 and can go up to $500 per offense. Those fines can add up quickly, so it’s best to just stay within the law when you make modifications.
Your NH Exhaust Team | Lou’s Custom Exhaust
A custom exhaust system can have a huge impact on your vehicle’s performance. At Lou’s Custom Exhaust, our team will design an exhaust system to your specifications while ensuring you stay within NH exhaust law.
