Noise Limit

Buggy924 · Powerhouse Poster

RE: Noise Limit

tumbleweed · Forum Junkie

We are talking two things here - event noise - and vehicle noise. Vehicle noise contributes to event noise and is the thing we can regulate. Event noise can be controlled by many means including limiting vehicle noise but also, track layout, intervals between cars, length of race and enviromental conditions. For some tracks an earth mound could fix a particular neighbours problem.

Event noise is what a neighbour could complain about. A test for event noise would include maximum readings but also what reading was exceeded more than 1% of the time, 10% of the time and 100% of the time. These are referred to as Lamax, La1, La10, La100.

I think you would find The Lamax numbers would be higher at a shooting range, or the reversing beeper on a mine ute but they are noises with a shorter duration. The La1 would be a more appropriate measure if you were to compare venues.

I am of the firm belief that if we are to regulate we need to design a test that can be replicated by the racer. Or we have a noise day where constructive feedback is given and tests performed with many cars in some form of identical setup. I dont have any experienc designing tests but maybe something as simple as two Oz trail 3mx3m gazebo's with plywood sides to a set height. Car at one end with exhaust facing in, standardised test unit at the other at a set height. Could that be replicated by a couple of racers getting together on the weekend? Would it be similar each time compared to a test in a race with enviromental considerations? Would it satisfy those that say we need to be seen to be doing something? Could you have that set up at scrutineering? (maybe not every race but strategic ones)

Patrol842 · Forum Addict

4000 RPM on a cast iron pushrod diesel engine is very different to 4000 rpm on a twin cam 1600.

Static test is pointless, you need some load on it to get the wastegate open and/or a decent amount of fuel in it.
Average readings of two fixed microphones a fixed and specified distance from the track, one on each side and halfway down a straight, and even then you're shooting in the dark because people can back off.

Protest your noise penalty until they can produce a calibration certificate and some form of certificate of competency for the operator. Their testing method is less accurate than measuring cage tubes with a stack soggy of beer coasters from the pub. I'm not exaggerating there.

Any equipment in the price range likely to be purchased by a racer for their own tests is not going to be accurate enough to be worth using. The CAMS standards do not specify a margin of error and their operators are clearly not qualified judging by their methodology. It's not the fault of the operator, they aren't being given appropriate tools for what they are trying to do.

I agree with the principle of the idea, but the method is so pathetic its embarassing. Give up the pretense and go back to "Hmm, Joe do you think that one is a bit loud?" "Yeah" "ok we'll give him a warning" it's fairer because people arent being misled by tools they think they understand.