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I'm tracking my Evora 400 with Race ASB bushings and de-cat pipe. Shes pretty loud, louder than a stock F-Type R from what I've personally seen.

Even with the higher sound limit, it seems I'll be pushing the sound limits and get flagged. I'd like to avoid reverting the back to stock and adding the 3rd de-cat.

Has anyone ran their Evora 400 w/ de-cat at Laguna (103dB) events with no sound violations?
 

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Not sure how Laguna does sound check but if you know where the meter is you just need to lift when you're passing it.
 

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Sound check is at turn 5 when you start going up hill. Don't know how you got an event with 103 db, normally for club events it's 90~92.
 

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103dB days are rare for Laguna track days, so probably not many with experience.

As one who has run afoul of the sound police at Laguna, a 103dB is day is a treat. As richthom says above, the sound booth is just past Turn 5 on drivers right at the point where you are WFO going up the hill. The lift strategy usually doesn't work well.

Check with the track day's/track's specific sound rules for the day. Weather can have a big effect on whether you go over the limit. There's no appeal process, no questioning of the sound meter calibration or the nature of birth of the person manning the sound booth...

Overcast/foggy cool mornings allow for the sound to reflect more from the clouds and the hills. The car is making more power too. A car that's good any other day could get dinged.
Hot sunny days mean less sound reflection and you might be OK.
Induction/intake supercharger noise will also affect sound. It has a cumulative effect on overall sound.
If you have a noisy gearbox (straight cut gears in a Hewland for example), that can also affect sound. (Learned the hard way when 3rd gear came close to failure)

103dBA is pretty loud, but pressure levels vary by frequency and tone. That's full open exhaust for a 2L production car race motor. You'll probably be OK, you might not.

I suggest you make up a turnout elbow that will clamp to your tail pipe and exit to the left of the car. That will save you 1-2 dBA. If you weld 3 each 3/4" flat washers in a triangle pattern over the end of the turnout, it may save you another 1dBA. If you have an open inlet like K&N cone filter, suggest putting the OEM airbox filter on, or at least bring it with you.

I saved my weekend by repacking my supertrapp muffler with fiberglass then clamped a galvanized clothes dryer vent elbow to the muffler outlet. YMMV.

Get out and have some fun. GGLC will be running the 2 mile track at Thunderhill on June 26, so there are more track opportunities coming alive.
 
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