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Quieter Exhaust on 20019 GT3 RS

 
Old 06-01-2019, 06:26 PM
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Bob Rouleau
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Default Quieter Exhaust on 20019 GT3 RS

Our local track is rigidly enforcing a 92dBA limit. My RS got busted. I have ordered Soul down pipes with resonators. Until they arrive I need a temporary solution. Is there any easy way to force the exhaust valves to stay in the quiet position? I found a simple trick for the 997 version but the 2019 is veery different. Other club members with GT3 and GT4 would also appreciate this trick if it exists.

Best,
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Old 06-01-2019, 06:35 PM
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TRAKCAR
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Ugh, even there now.

Its crazy that our cars are legal on the road but illegal on many races tracks.
A German shop made me this to try and pass local 86 dB tracks..

SOUL could work at 92dB depending on how and where they measure.
Might have to add some steel wool.




Last edited by TRAKCAR; 06-01-2019 at 09:02 PM.
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Old 06-01-2019, 06:42 PM
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WTH
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Old 06-01-2019, 06:50 PM
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Old 06-01-2019, 07:00 PM
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Dear Canadian time traveler, tell us the wonders of your civilization?!
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Old 06-01-2019, 07:04 PM
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Yeah, by 20,019 AD I suspect the internal combustion engine to be extinct.
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Old 06-01-2019, 07:14 PM
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Originally Posted by soulsea View Post
Dear Canadian time traveler, tell us the wonders of your civilization?!
http://getyarn.io/yarn-clip/1a7e3834-5956-423a-873d-7207cef81d6d
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Old 06-01-2019, 07:25 PM
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The Dundon quiet muffler might be the way to go for you.
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Old 06-01-2019, 07:33 PM
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These are suppose to cut sound by up to 5 dB. Should be enough to pass sound.

https://www.jcr-developments.com/por...d-exhaust-tips
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Old 06-01-2019, 09:34 PM
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Easiest solution is to find out where the sound mic station is located, and then lift or go into 2 gears higher than usual when you pass by it.
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Old 06-02-2019, 10:14 AM
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2 long pieces of rad tubing, use the bent tube, cut them and clamp them down towards the pavement. Simple trick, won't melt, bend if you hit something and will drop the sound wave big time. Been doing it to motorcycles for years.
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Old 06-02-2019, 10:53 AM
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Originally Posted by bli8
These are suppose to cut sound by up to 5 dB. Should be enough to pass sound.

https://www.jcr-developments.com/por...d-exhaust-tips
Those have allowed me to pass some notoriously difficult noise tracks in the UK. It's not just the dB limit; it's where and how many of the meters there are. The JCR solution has worked very well for me so far when I've seen other P-GT's sent home for noise.
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Old 06-02-2019, 11:14 AM
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Originally Posted by Bob Rouleau View Post
Our local track is rigidly enforcing a 92dBA limit. My RS got busted. I have ordered Soul down pipes with resonators. Until they arrive I need a temporary solution. Is there any easy way to force the exhaust valves to stay in the quiet position? I found a simple trick for the 997 version but the 2019 is veery different. Other club members with GT3 and GT4 would also appreciate this trick if it exists.

Best,
The stock 991 or 991.2 GT3 won't pass a 92 dBA limit at 50ft on the stock exhaust. The stock exhaust at 50ft is reading anywhere from 92 dBA to 101 dBA depending on conditions (wind, clouds, etc.).

The Soul Performance turn-downs are excellent, the resonated tips (which I use as permanent tips) reduce 2dBA at 50ft, and the turndowns another 2-3 dBA, but the car could exceed 92dBA even with these turn downs.

Using metal wire to keep the valves forcibly closed is dangerous to the engine, the upper path for the muffler flows through a 50mm diameter straw, whereas the lower path enters at 63mm and exits at 59mm. Despite of the 9mm difference, there is a 30% flow reduction due to the diameter of the system with the valves closed, and the stock exhaust is already restricted with the valves open (my car gained confirmed power by eliminating the stock side and center exhaust and installing JCR Silenced Race Pipes).

The solution for 92 dBA:

- Dundon Quiet Muffler + Dundon turn away or turn down pipes (depending on what's allowed, turn aways are being banned too).
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Old 06-02-2019, 11:15 AM
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Originally Posted by usctrojanGT3 View Post
The Dundon quiet muffler might be the way to go for you.

This
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Old 06-02-2019, 12:01 PM
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These Akrapovic silencers are the best looking ones I have seen. They were on a GT3 at Spa recently and looked pretty cool.



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