Laguna Seca & Exhaust Noise Levels
#32
Rennlist Member
^^^I need to invest in one of those also.
To answer earlier question, my exhaust is 100% oem before installing these tips. I've passed events in the UK <92db limit and at one particular circuit that has monitors EVERYWHERE and is a difficult 92. Ask anyone from the UK about Brands Hatch on a GP day; they are STRICT at 92 because the GP part of the circuit runs close to houses and the town hall has its own monitor in addition to MSV's. That's no g'tee it will work at another 92 dB circuit. But every other Gt3/RS was black flagged for noise and sent home the days i went. I was never even warned. Sorry, while I am moving back to the US this summer, no plans for Laguna Seca anytime soon. So, any "front line" testing will need to come from someone else good luck!
To answer earlier question, my exhaust is 100% oem before installing these tips. I've passed events in the UK <92db limit and at one particular circuit that has monitors EVERYWHERE and is a difficult 92. Ask anyone from the UK about Brands Hatch on a GP day; they are STRICT at 92 because the GP part of the circuit runs close to houses and the town hall has its own monitor in addition to MSV's. That's no g'tee it will work at another 92 dB circuit. But every other Gt3/RS was black flagged for noise and sent home the days i went. I was never even warned. Sorry, while I am moving back to the US this summer, no plans for Laguna Seca anytime soon. So, any "front line" testing will need to come from someone else good luck!
#33
Rennlist Member
FWIW:
I emailed Joe Kou when I first got my .1 GT3 because I wasn't sure if it would pass with a sharkwerks CMB even with track nanny and turn downs. This was what he told me for a GT3 with OEM exhaust:
"96-98dB with nothing
92dB with track nanny
88dB with track nanny and turnaway pipes"
My experience so far, all of the below WITH track nanny all on 90db days:
OEM sides - Sharkwerks - SP Motorsports turnaways: Fail
Valved side deletes - OEM center - Soul muffled turndowns: Fail
OEM sides - JCR silenced CMB - Soul muffled turndowns: Fail
All of the above blew a 94-95. One might be OK on a 92 db day because I've been told they let you slide a couple db. I'm tracking out of 5 in 3rd with my RPM starting in the 6700-7000 range. Just a slight hesitation on throttle and I'd pass with the last (and current) setup all day so it's very close for me. Hopefully I'll get a chance to drive a 92db day here soon.
I emailed Joe Kou when I first got my .1 GT3 because I wasn't sure if it would pass with a sharkwerks CMB even with track nanny and turn downs. This was what he told me for a GT3 with OEM exhaust:
"96-98dB with nothing
92dB with track nanny
88dB with track nanny and turnaway pipes"
My experience so far, all of the below WITH track nanny all on 90db days:
OEM sides - Sharkwerks - SP Motorsports turnaways: Fail
Valved side deletes - OEM center - Soul muffled turndowns: Fail
OEM sides - JCR silenced CMB - Soul muffled turndowns: Fail
All of the above blew a 94-95. One might be OK on a 92 db day because I've been told they let you slide a couple db. I'm tracking out of 5 in 3rd with my RPM starting in the 6700-7000 range. Just a slight hesitation on throttle and I'd pass with the last (and current) setup all day so it's very close for me. Hopefully I'll get a chance to drive a 92db day here soon.
#34
Rennlist Member
^^^u r running an x-pipe, no? Kinda defeats purpose of trying to meet noise limits of a quiet track. Gotta go oem + tail-pipe silencers with turn-down. Then u r about as quiet as you can get. And with 3 bolts u r back to oem.
#35
Rennlist Member
I agree, but the whole point of this thread is many don't want to run OEM exhaust all the time just for Laguna. And even the setup you mention above won't pass there reliably without GPS (Track Nanny).
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Ducati1199 (06-25-2019)
#36
Basic Sponsor
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These worked awesome for me
https://www.jcr-developments.com/por...d-exhaust-tips
A few 991 Gt3/RS sent home. I was WOT all day.
https://www.jcr-developments.com/por...d-exhaust-tips
A few 991 Gt3/RS sent home. I was WOT all day.
We have a ton of customers here in the UK running this set up lapping all day without issues, great to hear you’re experiencing similar success
JC
#37
Rennlist Member
A lot of the UK tracks have similar strict noise limits to Laguna so we have plenty of experience of this. Our silenced tips in combination with the factory exhaust will pass.
We have a ton of customers here in the UK running this set up lapping all day without issues, great to hear you’re experiencing similar success
JC
We have a ton of customers here in the UK running this set up lapping all day without issues, great to hear you’re experiencing similar success
JC
That means your silenced tips would need to drop the sound level 6-8 db to reliably pass at Laguna with no GPS. You know I love your stuff but I've got to question that.
#38
I'm going to this. Anyone know if a .2 RS with GMG center delete will be ok on a 103 event? I'm told by my shop that all the racers he supports are going with straight pipes during the same event. So do they not actually measure on 103 days? Seems to me that any straight pipe race car will go way over 103.
#39
Rennlist Member
Idk about 6 or 8db drops. Idk what oem exhaust noise levels are as a starting point. However, I’ve passed several 92db drive-by tracks at wot in the UK on 991.2 gt3 and 3rs w/oem exhaust and the jcr silencer tail-pipes with down-turn pipes. I don’t have any experience with them on anything other than oem exhaust; no experience w/them using a bypass or specifically at Laguna, but plenty of days at <92db where i drove all day long w/no warnings. Good luck; all these quiet circuits suck; at least you have a fighting chance with porsche; zero chance with ferrari. Someone sent me a link the other day for street cameras noise limit test spots coming to a theater near you. Pretty soon, all the after-mkt exhaust guys are going to switch to products that allow you to even drive your noisy antique anywhere! Sad days for sports cars
#40
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All I can say is here in the UK a 991.2 GT3 will blow limits by 5/8dB however with our Silenced Tips installed they pass no problem.
JC
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#41
Nordschleife Master
Originally Posted by RDCR
FWIW:
I emailed Joe Kou when I first got my .1 GT3 because I wasn't sure if it would pass with a sharkwerks CMB even with track nanny and turn downs. This was what he told me for a GT3 with OEM exhaust:
"96-98dB with nothing
92dB with track nanny
88dB with track nanny and turnaway pipes"
My experience so far, all of the below WITH track nanny all on 90db days:
OEM sides - Sharkwerks - SP Motorsports turnaways: Fail
Valved side deletes - OEM center - Soul muffled turndowns: Fail
OEM sides - JCR silenced CMB - Soul muffled turndowns: Fail
All of the above blew a 94-95. One might be OK on a 92 db day because I've been told they let you slide a couple db. I'm tracking out of 5 in 3rd with my RPM starting in the 6700-7000 range. Just a slight hesitation on throttle and I'd pass with the last (and current) setup all day so it's very close for me. Hopefully I'll get a chance to drive a 92db day here soon.
I emailed Joe Kou when I first got my .1 GT3 because I wasn't sure if it would pass with a sharkwerks CMB even with track nanny and turn downs. This was what he told me for a GT3 with OEM exhaust:
"96-98dB with nothing
92dB with track nanny
88dB with track nanny and turnaway pipes"
My experience so far, all of the below WITH track nanny all on 90db days:
OEM sides - Sharkwerks - SP Motorsports turnaways: Fail
Valved side deletes - OEM center - Soul muffled turndowns: Fail
OEM sides - JCR silenced CMB - Soul muffled turndowns: Fail
All of the above blew a 94-95. One might be OK on a 92 db day because I've been told they let you slide a couple db. I'm tracking out of 5 in 3rd with my RPM starting in the 6700-7000 range. Just a slight hesitation on throttle and I'd pass with the last (and current) setup all day so it's very close for me. Hopefully I'll get a chance to drive a 92db day here soon.
#42
Rennlist Member
It is, I can hear the exhaust close and reopen in my videos. Plus I run around on the street using the Track Nanny to force the valves open all the time and it works flawlessly.
None of my configurations I listed above (that all failed) is all OEM. I was hoping the JCR silenced CMB would pass in conjunction with the OEM sides / silenced turn downs / Track Nanny as the silencers on the bypass portion of the JCR are pretty good size but no joy. It's close but everytime I get a good run out of 5 I blow sound.
You advised me to leave it all OEM last year if I didn't want any issues. Problem is I got addicted to the 9K crack on the street! Proverbial "have my cake and eat it too" situation.
None of my configurations I listed above (that all failed) is all OEM. I was hoping the JCR silenced CMB would pass in conjunction with the OEM sides / silenced turn downs / Track Nanny as the silencers on the bypass portion of the JCR are pretty good size but no joy. It's close but everytime I get a good run out of 5 I blow sound.
You advised me to leave it all OEM last year if I didn't want any issues. Problem is I got addicted to the 9K crack on the street! Proverbial "have my cake and eat it too" situation.
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4pointslow (07-15-2023)
#43
Will a 987.2 Cayman S with catless headers and a GT3 steel center muffler pass 103db sound limit?
#45
Racer
Lol, this is getting complex.
Please raise your hand if you have the following and can pass sound at LS
Please raise your hand if you have the following and can pass sound at LS
- 991.2 GT3 ... and
- Side Deletes - Valved... and
- Stock/OEM Center... and
- Silenced + Turned Down Tips... and
- NO track nanny GPS