What is the proper way to measure the sound level of an exhaust? At what distance from the exhaust tip do I need to hold the meter? Do I measure the sound when the engine is idle or at some higher RPM?
Thanx,nomuken.
sound level of an exhaust
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Q45tech
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"An exhaust louder than 95 decibels is not street-legal in California, as is one not certified by the California Air Resources Board. A CARB certified piece of equipment will have a sticker on it in a visible location"
"So far, 37 referee stations have been set up in California where a ticketed motorist can get a test for the sound level of their exhaust system. A driver only qualifies for the test when he or she gets ticketed.
Once a driver has been cited, he or she can find the location of a testing station by calling (800) 622-7733. The test is not open to anyone without a ticket. "http://www.sema.org/images/32266.jpghtt ... /32267.jpg
This procedure specifies a limit of 95 dB measured 20 inches from the exhaust pipe outlet with the engine operating in neutral, typically at speed of 3000-5000 rpm. It applies only to passenger vehicles. It does not apply to motorcycles or to vehicles over 6000 pounds gross weight.
"So far, 37 referee stations have been set up in California where a ticketed motorist can get a test for the sound level of their exhaust system. A driver only qualifies for the test when he or she gets ticketed.
Once a driver has been cited, he or she can find the location of a testing station by calling (800) 622-7733. The test is not open to anyone without a ticket. "http://www.sema.org/images/32266.jpghtt ... /32267.jpg
This procedure specifies a limit of 95 dB measured 20 inches from the exhaust pipe outlet with the engine operating in neutral, typically at speed of 3000-5000 rpm. It applies only to passenger vehicles. It does not apply to motorcycles or to vehicles over 6000 pounds gross weight.
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C-Kwik
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Pay most specific attention to 21750.2(b). It basically says 95 dB max when tested using SAE procedure J1169, which I believe is 18 inches from the tip at the same height as the tip.
Also, I know of no law that requires a Catback to have CARB EO numbers. Otherwise, cops would be pulling us over here just on that alone. That and muffler shops would be non-existent here.
Pay most specific attention to 21750.2(b). It basically says 95 dB max when tested using SAE procedure J1169, which I believe is 18 inches from the tip at the same height as the tip.
Also, I know of no law that requires a Catback to have CARB EO numbers. Otherwise, cops would be pulling us over here just on that alone. That and muffler shops would be non-existent here.