Noise testing help please

[antnicuk]

I have just fitted a bigger turbo and down pipe and also a bigger mid silencer. On the old set up I was a little high on noise, around 104 on the static test at woodbridge.

I have borrowed a friends noise meter, its a radio chack one and it has 2 settings, A and C. It reads a lot lower on A than it does C.

Does anyone know what setting I should use, or what setting track day companies use for the static test?

[muckymotor]

I always use A on mine and it gives pretty much the same reading as the official checks.

[R5GTTGAZ]

On a track day put a bit of red tape showing your red line at 5k rpm then you won't have to rev it that high when being tested.

[antnicuk]

thanks, any place i have been to just say is it a car engine or bike engine, then its 4500 for a car and 7 for a bike, no matter what engine so i dont think that will wash, especially when i tell em its a rotary

[GreenV8S]

The (A) scale is weighted towards the frequency range that humans can hear. This is the one that most circuits will use. The (C) scale is flat across a wide frequency range. You'd use this for health and safety issues relating to hearing damage and that sort of thing.

[Chris71]

Just be warned - the last DIY noise check I did turned out to be substantially lower than the reading the MSV scrutineers took! Don't know which end the error occured (probably ours) but it shows they don't always correlate, so if it's close you might want to head over to your lcoal track for a second opinion.

[Baby Blue]

U ll be extremely lucky if u get away with red tape jokes , especially with any MSV ......they now have list of cars , which is hopelessly inaccurate and demand the revs it says on the list .................also supposed to be tested at 3/4 max revs 50 cms from exhaust/s ...........Oulton in April right up the pipes and no arguments whatsover, Snetterton 3 weeks ago insisted my engine was 3600 cc, when its simply not and demanded 90% max revs as result of daft list .........its becoming bit of a gamble !