DB levels for track days

DB levels for track days

Author
Discussion

CitySlicker

Original Poster:

315 posts

100 months

Thursday 1st August
quotequote all
I'd like to take the 991 GT2 RS on track but there isn't much information online regarding noise levels for static/ drive by sound checks. Does anyone know what these cars record for the noise tests? I think it's significantly quieter than the GT3s, but any info would be appreciated!

Cheers

ChrisW.

6,827 posts

262 months

Thursday 1st August
quotequote all
Static noise test limits tend to be 105dB whilst drive by noise check limits are around 98dB ....

It used to be that noise levels were calculated at 3/4 max revs but I was recently noise tested at Oulton Park (a static test) at the requested 4000 rpm in my 991.2 GT3RS ... which with standard exhaust tested at 92dB.

I would expect a GT2RS to be quieter ??

MarkM3Evoplus

825 posts

207 months

Friday 2nd August
quotequote all
What track are you thinking of?

Brands for example is pretty strict with 92 dB drive by.

There is an RMA day at Donnington soon, which has no noise limit

braddo

11,252 posts

195 months

Friday 2nd August
quotequote all
I expect you'll have no problem at all but it will be intresting to see if anyone has actual dB readings.

Try revving your car in neutral to see if it can get to 75% of your redline. I think - it will top out at less than 5000rpm because 991s and later have a factory limiter. This means your car gives a lower static reading than the usual measure (75% of redline) and so it will pass at pretty much any track. The turbos dampen the exhaust so drive-by limits are very unlikely to be a problem.

I reckon your car will be below 98db static and I think Thruxton is the only circuit in the country with a limit lower than that.



CitySlicker

Original Poster:

315 posts

100 months

Friday 2nd August
quotequote all
That's interesting that you registered 92 db in the gt3 albeit at less than half revs. It's giving me a glimmer of hope because I am looking at Thruxton which has a 90db maximum static noise test and while stationary the car isn't particularly loud especially if you keep the exhaust valves closed.

@Braddo A quick youtube search and it appears the car can be revved high whilst stationary. Although that's an interesting point, they must be kicking off a lot of cars these days that can't comply with the static test and they will only know how loud they actually are on the drive bys.

ChrisW.

6,827 posts

262 months

Saturday 3rd August
quotequote all
RPM Technic make a downward facing exhaust tip set for the 991 GT series which is easily bolt on / bolt off ... the engine / exhaust is obviously quieter when warm ... I think that would be as much as you can do but t be honest, if your exhaust is standard I can't imagine that you would have a problem.


WombleCate

135 posts

12 months

Saturday 3rd August
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Depending on where you live I’d recommend asking a local track for a static noise test.

While Thruxton would be a brilliant circuit for your car they have to be very strict on noise. Their neighbours make complaints, so, they have a low limit and they do enforce it.

I wouldn’t be confident your car would pass Thruxton’s noise.

Silverstone GP and Donington would also both be great and noise levels are more lenient.

gtsralph

1,229 posts

151 months

Saturday 3rd August
quotequote all
CitySlicker said:
That's interesting that you registered 92 db in the gt3 albeit at less than half revs. It's giving me a glimmer of hope because I am looking at Thruxton which has a 90db maximum static noise test and while stationary the car isn't particularly loud especially if you keep the exhaust valves closed.

@Braddo A quick youtube search and it appears the car can be revved high whilst stationary. Although that's an interesting point, they must be kicking off a lot of cars these days that can't comply with the static test and they will only know how loud they actually are on the drive bys.
I have seen a GT3 RS 991.1 pass the noise test at Thruxton. The tester is normally lenient with Porsches as they test higher at static v drive-by versus other cars given the rear engine and induction noise. You can always try JCR turn-down noise limiters which worked for me but other and far less expensive alternatives are available for occasional track days.

TDT

5,430 posts

126 months

Saturday 3rd August
quotequote all
CitySlicker said:
I'd like to take the 991 GT2 RS on track but there isn't much information online regarding noise levels for static/ drive by sound checks. Does anyone know what these cars record for the noise tests? I think it's significantly quieter than the GT3s, but any info would be appreciated!

Cheers
With the OEM exhaust system on 991 GT2 RS, you should not have any sound metering issues anywhere.
That’s not to say the 2RS isn’t loud in its own way.. I love the aggressive, ‘p*ssed off’ rumble they have… but it’s not the same as N/A wailing.