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      05-01-2018, 06:23 PM   #1
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Sound violations at Weathertech (formerly Mazda) Raceway Laguna Seca

The legendary Laguna Seca track has new ownership, new management, and new rules. The sound limit is now 90 db. I learned this the hard way at an HPDE held this past weekend by the Golden Gate Chapter of the BMW Car Club of America (BMW CCA). I don't know what the old limit was, but I've run here two times previously, the last time in March 2017, with the same M4 with an M Performance Exhaust, and never had a problem running with the throttle in Sport or Sport+ mode.

On Saturday during the first session it is customary for an instructor to drive your car for the first 2 or three laps at about 60-70%, just to see how your car brakes and handles, and to spot any potential safety issues. My instructor, a good friend of mine who also owns a highly modified M4 ZCP, did 3 laps and then handed the car over to me.

My M1 button in my Track profile is set to Sport/Sport+/Comfort. I pressed M1 and headed out for my first lap. I was doing a warm-up lap at about 80%, and I came out of Turn 5, powered up the hill to Turn 6, came out of the corner and the flag stand on the left side of the track just past Turn 6 was displaying the black flag with an orange circle, the "Mechanical" flag, commonly known as the "meatball" flag. I came into the hot pits and checked in with the starter and he indicated that I had registered 93 db! My first session was over with less than one full lap! You get three strikes, and after the third strike, you're out...for the rest of the weekend! This was strike 1.

At our A group class meeting after the first session, I found out that the two Porsche GT4s in our group were also over the 90 db limit with a stock exhaust. Later, another M4 with an MPE in the D group also exceeded 90 db. There were several M3/M4 Competition Package cars with stock exhausts that didn't exceed the limit.

After some discussion with various people, I decided to modify my M1 button to set Throttle to Efficient mode, short shift after Turn 5, and maintain an even throttle until I passed the sound booth, which is on the right side of the track, just past Turn 5. With this strategy I made it through the second session, running up the hill in 4th gear (DCT).

During my third session, again on my first lap, I was running up the hill in 4th gear and once I passed the sound booth, I stepped on it before I had to slow down and downshift for Turn 6. The exhaust went "BLAT", I came around Turn 6, and there was the meatball flag again! Apparently, the microphones in the sound booth aren't fixed, and they can scan up the hill as a car passes. Strike 2 and I was done for the third session. My car is Sakhir Orange and it pretty much stands out on the track, so I'm pretty sure that the county employee that was manning the booth was looking for me each session.

I made it through the fourth session on Saturday by immediately upshifting all the way to 6th gear even before I reached the track out point for Turn 5. It took most of the fun out of Turns 5 & 6, but at least I lived to run again on Sunday!

I made it through all four sessions on Sunday using the same strategy. There was some discussion that there was a different person in the sound booth on Sunday, and that maybe they were being more lax. As we were getting towards the end of the fourth and last session I waited until I was pretty sure that there was only 1 lap left before the checkered flag. As I was coming into Turn 5, I switched to my M2 button which has Throttle set to Sport+, and blasted out of Turn 5, upshifting to 4th, 5th, and 6th. I came around Turn 6 and there was no meatball flag! We got the checkered flag by the time I came around to the start/stop on the main straight so we were done for the weekend.

After posting about this on Facebook on Saturday, a friend who runs his Cayman there with the Porsche Club, told me that some of the Porsches that run at Laguna Seca have a arduino-based exhaust control systems that use a GPS shield to determine their position and open/close their exhaust flaps accordingly. This is a brilliant solution and I'm going to look into whether any of the aftermarket M3/M4 exhaust flap controllers can do this or be modified to do this. Has anyone heard of a system that can utilize GPS data to open/close the exhaust flaps?
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      05-01-2018, 11:20 PM   #2
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I'm pretty sure it's always been 90dB, but depending on the time of the day and temperature, the sound may travel a bit more and cause you to blow sound when you normally wouldn't. Pretty easy fix though, either buy an electronic valve controller and close your exhaust valves or if you want to save some money just unplug your valves while they're closed so they will stay that way until you plug them back in.

My catless downpipes + akra evo with valves closed nets around 92dB, so you should definitely be fine with just the MPE and valves closed. I switch back to the stock zcp exhaust + catless downpipes and never have any issues with sound with the valves closed. Sucks to not hear your car as well, but such is the price of Laguna.
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      05-02-2018, 09:44 AM   #3
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my brother was at that event driving my 18 ZCP in Sport (not sport+), and didn't have any issues going up the hill. it's possible that his instructor just had him keep maintenance throttle going up the hill, then get back on it after turn 6. i thought that the sound meter was pointed perpendicular to the track, so scanning up the hill is new to me.

some tips/tricks from the Hooked On Driving folks for sound:
-As you pass under the bridge, go off line a bit towards driver's left
-Maintain moderate RPMs going up the hill until clear of the sound booth
-Note the weather conditions and drive accordingly (i'm not an acoustics engineer, but apparently overcast, humidity, temp all impact the pressure wave, and you might get some lee way on a day w/ the right conditions).

def sorry to hear you got meatballed
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      05-02-2018, 11:06 AM   #4
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Rather than worry about a GPS based exhaust flap control, why not just keep your exhaust flaps closed for the entire session/weekend? Closed exhaust flaps will make little, if any difference in HP/torque, and will keep you from getting flagged.
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      05-02-2018, 11:31 AM   #5
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Quote:
Originally Posted by SD ///M4 View Post
The legendary Laguna Seca track has new ownership, new management, and new rules. The sound limit is now 90 db.
It's been 90db for some time for "standard" days. The track gets a certain amount of >90db days per year, but it's like more than $15k extra to get one of those slots.
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      05-04-2018, 07:11 AM   #6
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I miss living in PG and hanging out at the track
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      05-04-2018, 07:16 AM   #7
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I miss it as well. The Monterey Cycling club hosted a monthly cycle (bicycle) around the track. Going around Laguna Seca on a bicycle was pretty weird, but lots of fun. Corkscrew was still crazy, even on a bike.
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      05-08-2018, 10:20 PM   #8
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Cant you drive on the opposite side of the sensors on the straight? Most people place an exhaust tip pointing the opposite direction which helps.
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      05-11-2018, 06:11 AM   #9
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[VENTING]

I just came back from the May 9th ETD day at laguna and I must say I'm fucking pissed at the sound bullshit nonsense!!!!!!!!!!!!!!!!! had to lift every time between 4-5 and its just such a sucky, draining feeling.. watching the seconds tick by as you coast through that bullshit sound booth built to please some fat ass richy idiots .. I hope that they have massive irritable bowel syndrome for the rest of their lives!

PS - WOT with flaps closed on a remus with mid pipe is still too loud (got meat balled at 92db) ..

Why do we have to put up with sound bullshit nonsense at a track day!!! @#*$(#@*$(@#*%@#%@#)$*#@)$*:mad0 259:

[END OF VENTING]
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      05-11-2018, 12:48 PM   #10
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Quote:
Originally Posted by trackm4 View Post
[VENTING]

I just came back from the May 9th ETD day at laguna and I must say I'm fucking pissed at the sound bullshit nonsense!!!!!!!!!!!!!!!!! had to lift every time between 4-5 and its just such a sucky, draining feeling.. watching the seconds tick by as you coast through that bullshit sound booth built to please some fat ass richy idiots .. I hope that they have massive irritable bowel syndrome for the rest of their lives!

PS - WOT with flaps closed on a remus with mid pipe is still too loud (got meat balled at 92db) ..

Why do we have to put up with sound bullshit nonsense at a track day!!! @#*$(#@*$(@#*%@#%@#)$*#@)$*:mad0 259:



[END OF VENTING]
were you in a white M4 in B group? i was in the same run group (black F80 w 513M wheels). def seemed like the fog layer and humidity were causing a lot more meatballs.
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      05-11-2018, 04:34 PM   #11
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Quote:
Originally Posted by dth656 View Post
were you in a white M4 in B group? i was in the same run group (black F80 w 513M wheels). def seemed like the fog layer and humidity were causing a lot more meatballs.
Sweet - yeah that was me .. I got meat-balled in the first session with my valve closed and maintenance throttle because i shifted up from 3 to 4 right at the sound booth and my car "farted" hahahaha.. Then I got meatballed in the last session because I was in a fuck-it-I'm-going-full-throttle mood..
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      05-11-2018, 09:12 PM   #12
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Quote:
Originally Posted by trackm4 View Post
Sweet - yeah that was me .. I got meat-balled in the first session with my valve closed and maintenance throttle because i shifted up from 3 to 4 right at the sound booth and my car "farted" hahahaha.. Then I got meatballed in the last session because I was in a fuck-it-I'm-going-full-throttle mood..
yeah, the guy in the blue E46 w/ the baffled pipes aimed left (laguna specific) took them off for the last session and went full loud, ha.

first time in a RWD car, i was def off the pace. hopefully more practice and i get used to the F80 and i can keep up w/ you guys!
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      05-12-2018, 11:49 PM   #13
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Hey man I got meatball'd too for doing 93 dB cause of an exhaust fart. my only solution afterwards was to stay far left, upshifting early, switching to efficient mode, and keeping it under 4k RPM.
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      05-12-2018, 11:57 PM   #14
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Quote:
Originally Posted by aajjcc View Post
Hey man I got meatball'd too for doing 93 dB cause of an exhaust fart. my only solution afterwards was to stay far left, upshifting early, switching to efficient mode, and keeping it under 4k RPM.
same here! I stay in 4th coming into t5 and I don't downshift.. I just stay in 4 up through t5 downshift to 3 right after I pass the bridge then accelerate hard up the hill ..

I'm going back on the 25th.. I figure take one second out of my lap-time to calculate my laptime if I'd stayed wide open. I figure I lose about a second going up that hill on maintenance throttle.
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      05-13-2018, 06:33 PM   #15
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Exclusive Track Days has a 105 dB day on July 16th.

90 dB is the cheapest option, and a track organizer can pay extra to get that bumped up to 92 dB. I never had a problem with my stock ZCP muffler on my F82, even at the top of 3rd.

105 dB sounds like an unlimited day right, but they still measure, lol. In my E46, I was blowing 107 dB! I had to short shift to 4th to avoid the meatball.
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      05-16-2018, 12:26 PM   #16
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[QUOTE=redpriest;23187719]I never had a problem with my stock ZCP muffler on my F82, even at the top of 3rd.
QUOTE]

Do you know of anyone having success with stock ZCP muffler and AA mid-pipe?

I was talking to guy who said he runs fast advance at LS flat out everywhere in stock ZCP with no issues at all and always passes 92DB limit.
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      05-16-2018, 01:15 PM   #17
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Quote:
Originally Posted by 5thgear View Post
Do you know of anyone having success with stock ZCP muffler and AA mid-pipe?

I was talking to guy who said he runs fast advance at LS flat out everywhere in stock ZCP with no issues at all and always passes 92DB limit.
Downpipes, stock ZCP, valves closed - passes 90dB no problem. Running WOT in Sport+ hugging the right hand side closest to sound station.

Downpipes, full Akra Evo, valves closed - 92-93dB. Running WOT in Sport+ hugging the right hand side closest to sound station.
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      05-16-2018, 01:47 PM   #18
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Quote:
Originally Posted by Continental02 View Post
Downpipes, stock ZCP, valves closed - passes 90dB no problem. Running WOT in Sport+ hugging the right hand side closest to sound station.

Downpipes, full Akra Evo, valves closed - 92-93dB. Running WOT in Sport+ hugging the right hand side closest to sound station.
Thanks for info.

Just to clarify, how do you run valve closed and be in sport+ WOT?

I cant imagine M performance exhaust is louder than downpipes with akro so if this works, how comes OP got flagged with M performance exhaust. I am sure I missing something.
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      05-16-2018, 03:10 PM   #19
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What about non-ZCP, in Sport+ plus with open valves at WOT?
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      05-16-2018, 03:42 PM   #20
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Quote:
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What about non-ZCP, in Sport+ plus with open valves at WOT?
What are you guys saying 92db? Most days at Laguna Seca are now 90db .. 92db days are very rare.
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      05-16-2018, 06:09 PM   #21
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Quote:
Originally Posted by trackm4 View Post
What are you guys saying 92db? Most days at Laguna Seca are now 90db .. 92db days are very rare.
Very interested in an answer for 92DB because speed ventures have a 92DB event end of next month June 29th to July 1st.
The weekend after that PCA have a 92DB weekend.
The weekend after is also 92DB.
Then first week of August Porsche owners club also 92DB.
Skip into October then another 92DB weekend with Alfa Romeo club.
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      05-16-2018, 06:36 PM   #22
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Quote:
Originally Posted by 5thgear View Post
Very interested in an answer for 92DB because speed ventures have a 92DB event end of next month June 29th to July 1st.
The weekend after that PCA have a 92DB weekend.
The weekend after is also 92DB.
Then first week of August Porsche owners club also 92DB.
Skip into October then another 92DB weekend with Alfa Romeo club.
oh wow this is awesome, I didn't know! .. coolness! Though I've never run with the local PCA chapter.. I heard PCA can be a bit pain-in-the-ass with tech and checklists etc.
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