Born on the streets of Oakland, California, whistler exhaust tips are pieces of metal welded into the tip of a car's exhaust pipe that emit a high-pitched shriek under acceleration. The sound is said to be similar to the sound of a rail-car slamming on its brakes, or a rusty door-hinge, and is almost universally hated by all but those who have them.
Exhaust whistlers have long been used as practical joke devices by sadistic and savvy mechanics. The mechanic would install the whistler far inside the exhaust pipe of his unwitting victim's car and sit back and enjoy the sound of insanity as the victim tried in vain to figure out where the sound was coming from. It has only been fairly recently that whistlers have become a fashion statement, having been popularized by such rappers as T-Pain and Snoop Dogg.
Tailpipe whistlers start as 1/8-by-1.5-inch steel plate, through which is drilled a 1/2-inch holes, and is rounded off on the edges to fit inside a pipe. A larger hole yields a lower-pitched sound, but requires a larger displacement engine to work. The whistle is welded anywhere from 1 to 6 inches inside each tailpipe and is generally visible from the outside.
Whistle tips are generally most popular in urban areas, particularly those on the west coast of the United States and are currently enjoying a surge of popularity in New England. Demographics (provided by Orlando based Consumer Demographics) suggest that the average whistle tip owner has spent at least 17.5 months in jail, works in the service industry, has two children and drives a Chevrolet, Ford or Toyota costing less than $900.
Though some maintain that the whistler tip has no effect whatsoever on the vehicle, that fact depends largely upon the vehicle in question. Since these tips block a large percentage of the exhaust tip area, they almost universally inhibit flow. This can lead to loss of power, lower fuel economy, engine overheating and premature failure of emissions equipment and oxygen sensors.
Whistler tips have, almost without exception, been outlawed in every area in which they have become popular. This first occurred in the city of San Leandro, CA, when the city's vehicle noise ordinance bill was altered to include vehicles that "contained any device whose sole feature is to make the vehicle louder and present a public nuisance." (Division 12, Chapter 5, article 2, section 27150.3)