Passing sound at Laguna Seca

**Sprockett88** · 02-03-2020

I have a bone stock '13 GTS. Can anyone with experience tell me what is required to pass sound at a 90db day at Laguna?

**TheWessss** · 02-03-2020

The simple answer is you just life off the gas as you pass the sound booth. My ACR-E with headers, no cats, & arrow PCM went well North of 100db if I didn't lift. You may be close with a stock, but the side exhaust will not help here. Remember if you go over 90db you get black flagged and that session is over for you. You could do one lap at the end of your first session without lifting and see if you went over the limit. That way you will know and it won't cost you a whole session, like me. Have fun, its a great track, don't forget about Thunderhill too, just as good.

**RickyBobby** · 02-03-2020

Stock Gen 5 without any changes to mufflers or cats can pass sound of a 90db day by doing one of two things as you approach turn 5 uphill right hander by the soundbooth between turns 5-6 (only spot sound is measured on track, microphone about 70-100 ft. off the track on the right).

1. Upshift into 4th which will lower your RPMs as you chug uphill but will reduce the amount of decibels.
2. Hold 3rd gear but limit RPMs to about 4000-4500 RPMs. If it is a cloudy, damp, or slightly humid (rare) day sound will get trapped and use the 4k guideline.
3. Once you're past the microphone you can start to roll on throttle (don't get on it yet) and accelerate out up the hill.

You'll be about 2-4 seconds slower per lap vs. a high decibel day but you don't have to run Laguna Pipes like most other cars will need. Turn 5 through Turn 6 where the soundbooth is at is a terrific passing zone with high HP cars like ours, resist the temptation and you'll pass sound as there are many other areas to pass on this track.

**Sprockett88** · 02-03-2020

Thanks for the reply and yeah, lifting is always an options but if I wasn't clear, I'm searching for known exhaust solutions for passing sound with a stock Viper if such exists. Like, will a simple turn down do it or are we a long away from 90? I'm assuming we are further away than that. Has anyone fashioned a Supertrapp tip onto the oem? Should I be bother thinking about both sides of the car or just work on the right?

If stuck essentially lifting, is it possible to just to upshift and stay left at the booth like some of the Porsche guys seem to get away with?

**Sprockett88** · 02-03-2020

Originally Posted by RickyBobby

Stock Gen 5 without any changes to mufflers or cats can pass sound of a 90db day by doing one of two things ...

Thanks! To clarify the 4th gear suggestion...are you saying we can go 4th and remain full throttle to the bridge?

**RickyBobby** · 02-03-2020

I've ran Laguna on my Gen 5 for about 5 years now and have yet to find a any gen Viper run Laguna pipes or pack steel wool or any of the other tricks the other cars have to do. It's actually not that bad lifting once you get the hang of it. Most Vipers don't run low decibel days and just wait for the high db days. I think the only cool solution I think could work is the mechanical exhaust valves setup (GPS enabled that close valves before turn 5 and open them up after the soundbooth) that some of the GT3 guys run. The problem with Laguna pipes on our cars being side setup is that if your turn it down towards the ground you're now bouncing sound off the pavement which creates louder db. If you point it up, now it's pointed towards your door or rear fenders which generate heat.

**RickyBobby** · 02-03-2020

Yes you can stay on throttle using this method but I've found that once you're past the soundbooth your car starts bogging uphill and forces a downshift into 3rd gear so your car can start accelerating for another fast uphill right hander on turn 6.

If you hold in 3rd but limit RPMs, it eliminates a downshift.

I actually use both methods.

**serpent** · 02-03-2020

Originally Posted by TKO MOTORSPORTS TEAM

Wait for 105DB day.... they do exist for amateur open track days at laguna now. Lifting at the sound booth sometimes doesnt work depending on the open track day. Unfortunately the county got wise to the lifting at sound booth about 10 years ago. Some of the bigger track days or when they feel like it the county sends out a " sound inspector" who walks around listening with a " trained ear" and if he feels your to loud you get the meat ball. Lots of politics and MONEY behind the sound rules at Laguna.

I got red flagged near the end of my 2nd session since i was WOT by the sound booth. After that I just let off by the sound booth area. WOT every where else. Not a big issue.