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BCCR 9.14.1 Noise Limit - List of tracks with noise regulations

Bill Strong

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9.14. NOISE LIMIT 9.14.1. ChampCar’s basic noise limit for FOR ALL EVENTS is 96 dbA at 50 feet from the track. Certain events may impose a tighter noise restriction – check all event supplemental rules. Excessive noise will result in a black-flag and require repair prior to being readmitted to the race. A second offense will result in disqualification and removal from the event.


Please note that all ChampCar events will have a 96 dbA limit. Enforcement is up to the ChampCar Race Director.


  • WEATHERTECH RACEWAY LAGUNA SECA - 90 dbA at 50 feet from track edge   
    <Notes: Point exhaust up and to drivers left. Sound meter at T5 and T6. Intake roar can affect your sound levels. Box that air filter.>


  • CALABOGIE MOTORSPORTS PARK - 92 dbA at 50 feet from track center   
    <Notes: They will be very strict on sound limits. >


  • NCM MOTORSPORTS PARK - 96 dbA at 50 feet 
    <Notes: Sound meters at various places. Cloud layer can affect the levels. What works today and deflecting sound may not work tomorrow. Just add mufflers>


  • THOMPSON SPEEDWAY - 96 dBa at 50 feet (track limit is 103 dbA - but, ChampCar uses 96 dbA)


  • ATLANTA MOTORSPORTS PARK -  98 dbA at 50 feet from track edge, inside and outside for cars (ChampCar uses 96 dbA)


  • HARRIS HILL RACEWAY - 99 dbA trackside and 85 dbA at the property line, (ChampCar uses 96dbA trackside)



Sound testing per Calabogie Motorsports Park - (ref: https://www.calabogiemotorsports.com/wp-content/uploads/2018/08/guidelines1small.jpg )

  1. Stationary Test -  Sound levels will be measured 15 feet in front and behind the vehicle while the engine is revved at 2/3rds of redline of tachometer.  Cars, the average should be no more than 100 dbA with no single reading over 104 dbA.
  2. Pass-by Test - With the vehicle under full acceleration on the track, a reading will be taken from 50 feet. The maximum level allowed is 92 dbA.



How is car noise measured? (ref: https://catdrivertraining.co.uk/track-day-noise-limit-guide/ )

Vehicle noise levels are measured using dB(A), a decibel reading that has been weighted to take into account the perceived loudness of a sound. The measurement is taken using a Decibel Meter, a gadget you can buy easily online to get an idea of what ballpark your car’s dB(A) reading is.

There is also a range of decibel meter smartphone apps, however, despite perhaps giving you an indication, you can’t rely on these readings 100% as track day readings will be impacted by various factors; surroundings, air pressure, air moisture and temperature can all affect what measurement is read.

To avoid disappointment, we recommend speaking with your track day organiser or even the circuit to seek advice based on your vehicle set-up. Some tracks will give you a free test prior to the track day.


ATV sound test document - some good explanations of how to conduct your own testing.



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  • 1 year later...
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Some useful links.

It's always good to have some spare bents and exhaust piping in the trailer to fix issues at the track.

Side-pipe hookup kits are awesome at allowing different ways of making exits or even fixing crash damage.
They come in various flavors, 2.5" and 3" for some cheap money. Looks like 3" is out of stock. These are slip-fit mandrel bends with exhaust clamps, so no welding is needed.


Having a couple of these combo bends is a great way of getting that "just right" bend.


I am showing 2.5" exhaust, and I know that goes against every instinct to use big pipes on race cars. But the smaller pipes can also be quieter when it comes to the sound that the track is measuring. 2.5" is a good compromise when it comes to reducing back pressure and keeping sounds low. 
As with any racing car, it's always good to build two systems for your car, one on it,m and one in the trailer or pickup to fix damage either during the race, or after.  I find buying these kits is super cheap and makes fixes easy.


Exhaust flange gaskets. 
After years of testing on the V6 MR2, I found different ways of making a very reliable flange setup for endurance racing.
The most reliable setup was the Chrysler/GM style ball and socket flange. Heavy and costly, they are the most bulletproof setup I have ever used. These make great exhaust adapters where you can adapt dis-simular exhaust diameters, like make an 89db Laguna exhaust system, and when you race at Willow Springs, you can easily put your 96db exhaust on.

Header collector or general exhaust gaskets. 
I have used the supplied gaskets for headers, and for the most part, they failed almost within the first stint. Especially the Chinese manufactured "eBay/Amazon" stuff. I have successfully welded new American-made 3-bolt flanges onto my Chinese headers, and had about a 1/2" overlap on the joints, and combined with the copper gaskets made a pretty bulletproof setup. It's not perfect and doesn't take to moving around well, without some sort of flex. I also double-nut the bolts. Drilling the nuts and safety wiring them also works well.
https://www.speedwaymotors.com/Search?query=exhaust flange&facet=l_material_type:79


V-Band interlocking clamps.
I started using these clamps a few years ago. Good ones are not cheap. But they are pretty damn reliable if you use them in conjunction with flex joints.
These slip over the pipes, and always have an overlap to act as the gasket.


Exhaust pipe flex tubes. 
My experience in my cars has shown that the ball and socket is the best for my racing applications. But sometimes money and maybe the location of the needed joint does not allow the use of one of those. 
I found that the typical wire-wound flex is good as long as the inside is not braided wire. Those cheaper versions failed after one of two race events. Having an interlocking smooth inner section like this is much better and does last much longer. For me, it was about a season of endurance races(10 or so).

Trailer tools.
Of course, everyone wants to do this racing stuff on the cheap. One of the best tools to load into your toter home and 40' triple stacker trailer is a welder. It's always good to have a tool to fix those pesky exhaust leaks that can keep you from racing. Welding with a MIG welder is not that hard to learn. Can you weld dimes as you see all over the internet? Hell no. But you can easily learn to MIG weld your exhaust to easily pass sound. Of course, your buddies that hang out in welding groups on the Internet will frown upon the tool I am going to post up. You can easily spend five figures on welders, and the more pricey welders are going to probably make the job easier, and look better. But for just over $100 you can get a Flux MIG welder that can do a good job at field welding parts on your race car. Flux wire does not require a bottle of gas, can actually get better penetration, and works awesome in outdoor windy conditions. It's not a pretty weld like you see on the Internet. But it works. And remember, even if you don't know how to weld, there are 20 others in the paddock that can do it as long as there is a welder to use. It operates on 110v power. It won't weld thick stuff in one pass, but for the exhaust pipe, it does a wonderful job.
t some good gloves, an auto-darkening helmet, and a roll or two of flus-core wire, and some good wire brushes. All that can be had for under $200. 

Exhaust hangers and clamps.
Those clamps that you connect the pipe up with can hang down pretty low. Racing can take you places that might be good to those low-hanging bits on your car. They can dig into the dirt, which can catch on curbing, and when that happens, that can weaken the joint, and cause the exhaust to hang, or just fall off. Keep the threads and nuts at an angle of at least 90 degrees to the ground. 
Your muffler with its flat face can catch stuff too when you get off-road, or even on curbing. I weld a 16-gauge steel sheet to the leading edge of the muffler to act as a ramp. This can also make the underside of your car more aerodynamic. Remember that it may be a good idea to add a ramp to the back of the muffler too. Your car may not always be moving with the nose forward.

mufler ramps.png


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  • 4 months later...
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Per our contract, Road America requires all race cars to have mufflers.

ChampCar limit of 96dBa is still the limit.

Track map within the supps will show sound reading location. 

plan your exhaust exit accordingly.


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