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Discussion Starter #1
Hi,

Major issue with my local track: max 95db allowed during track nights (what I mostly do)... which is impossible to meet with my (great) GMS 3" exhaust :oops:

=> I am looking for a good & efficient solution that would be easy to install when I arrive at the track (thus not another exhaust module)

Do you have any good experience to share with removable silencers or db killers that work amazingly / pretty well / slightly / really not ?

Thanks for your advise :)
 

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I think if we get @Call me Al into the conversation, he had them (but attached to his custom centre-exit large pipe exhaust).

Doubt that I can find the post, but he will remember what they are called, and be able to give you a review / tell you the ins and outs of them.
 

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There is a track here in the USA that is known for their strict control on sound limits. Most drivers use a "turn-down" or "turn-out" temporary add-on to the end of their exhausts. Basically, they are pointing the exhaust to the ground or away from the sound stations. You can find some examples by image searching "laguna seca exhaust turndown" or "laguna seca exhaust fixes".
 

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Found the original post for you :

 

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Hi,

Major issue with my local track: max 95db allowed during track nights (what I mostly do)... which is impossible to meet with my (great) GMS 3" exhaust :oops:

=> I am looking for a good & efficient solution that would be easy to install when I arrive at the track (thus not another exhaust module)

Do you have any good experience to share with removable silencers or db killers that work amazingly / pretty well / slightly / really not ?

Thanks for your advise :)
If the track stewards are cat lovers
108665

or maybe this
108667

...sorry LONG DAY :p
 

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Salut OLO,
I thought it sounded quiet good on monday 😉.
I saw a lot of Lotus guys using them during the day. Maybe look into the Lotus world for this?
Or Rudi @GMS could find one fitting his exhausts?
 

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Discussion Starter #11
I thought it sounded quiet good on monday 😉.
I had to slow down at every or the 3 🎙
The only time I accelerated very gently a bit too early from the 🎤 I was stopped by the track Marshall for excessive noise 😭
 

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Discussion Starter #12
Most drivers use a "turn-down" or "turn-out" temporary add-on to the end of their exhausts. Basically, they are pointing the exhaust to the ground or away from the sound stations.
tuening to the ground might be interesting. Turning away is not possible as the 🎤 are in both sides ;-)
 

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Interesting !
But if I understand correctly you built a specific part for that purpose, so not really plug&play ?
These would be relatively easy, except we have a dual exit GMS exhaust and I think the pieces are too close together to put two of these disks on the ends.
Call me Al's was a straight pipe 3", so adding a 3" disk silencer to the end would have been plug & play for him.

I didn't see anything ideal on their website.

If you add a pair of custom turn-downs to the GMS exhaust tips, be sure they fit very well or you'll be searching all over the track for them (as well as being too loud, when they fall off)!
 

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Discussion Starter #17
These would be relatively easy, except we have a dual exit GMS exhaust and I think the pieces are too close together to put two of these disks on the ends.
Call me Al's was a straight pipe 3", so adding a 3" disk silencer to the end would have been plug & play for him.

I didn't see anything ideal on their website.

If you add a pair of custom turn-downs to the GMS exhaust tips, be sure they fit very well or you'll be searching all over the track for them (as well as being too loud, when they fall off)!
Also what I thought !
 

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Stock 4C with race exhaust is measured at 95dB on idle. Your GMS 3" spec'd exhaust was producing 96 dB, so nat far off. A simple dB silencer should do the job. On a trackday with 95dB limit not much of high end NA cars will be seen. All GT3 RS series from 997 onward are way above that in stock form. Lambos and Ferraris are even louder with 458 being the absolute winner with roughly 100dB on WOT.

In your case I'd use these: Exhaust 3.5" Jap Can Silencer DB-Killer | Exhaust Parts UK. Simple bolt on solution that can be cut to custom length or use small diameter and push it through the tips in to the rear silencer. Ugly as ****, but it should keep the marshals of your back. For the hot lap just pull them out and do a hot lap before you get disqualified. 😁

Personally I prefer a bit more "expensive" events. Not because I like to spend money, but because the more expensive the trackday, the less the participants, more driving, more skilled drivers, less limitations, better cars and less crashing. On cheap events there is too much cars on the track at once and usually crazy drivers doing all kind of wicked stuff or racing to death until crashing into the barrier or in to you. In Grobnik where I drive the most, you just don't go with car worth more than 5k€ to open events if you car about your car or yourself.
 

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Discussion Starter #19
Thanks Rudi.

Just a precision: I was measured at 96db when I was gently starting to accelerate very quietly at 50m from the 🎤... not just next to it at normal throttle... or I would have been measured at 110db :LOL:

ill try an ugly solution, hoping that it’ll work.
Another 4C fellow uses Devil Decibel with his aftermarket exhaust and he pretends to reduce by +/- 10db.

apart from the noise limitation, track nights in Spa are perfect events: limited number of participants, open paddock, and real gentleman driving under strict monitoring with flags. I did several laps without meeting anyone, which was almost boring ;)
 
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