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Laguna Seca noise restrictions and Challenge cars...

Discussion in 'Challenge/GT Cars' started by rob lay, Mar 22, 2004.

  1. rob lay

    rob lay Administrator
    Staff Member Admin Social Subscribed Miami 2018 Owner

    Dec 1, 2000
    51,475
    Southlake, TX
    Full Name:
    Rob Lay
    From the www.fca2004.com website...

    Laguna Seca Raceway is a Monterey County Park. As such, it is governed by strict regulation for maximum sound levels permitted. We have negotiated the highest available limite of 103db for all 3 days of our track rental. We recommend you begin planning for how you will meet the sound limit. Sound levels are monitored by a Monterey County sound station, positioned on the outside of the track between turns 5 & 6. It is manned by county personnel (at our expense) and they have the ability to shut down the event if sound levels are exceeded. Some participants had difficulty with this in 1994 because they did not adequately prepare. We'd hate to see you bring your car across the country only to be told you can't run because its too loud. But, it CAN happen. Our advice at this time would be to prepare your car for 103db and be prepared to do more, if necessary. Weather conditions can impact the sound levels measured.

    I know the normal 355 challenge exhaust would exceed 103 db most of the time. My question is what exhaust setup the Challenge series used when racing there and what Db's were coming in?

    Thanks,
    rob
     
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  3. Hubert

    Hubert F1 Rookie

    Jan 3, 2002
    2,642
    The Left Coast

    Not ferrari specific, but for opentrack events, the dB limit is 93dB and lately has been as low as 90dB. A lot of the radical guys, and us with loud, openexhaust street cars, do is to clamp on baffles and elbow joints that point the exhaust away from the sound tower/dB meter. Also, if your car is helplessly loud -with said changes- you'll simply have to lift as you pass the moving dB meter, and on the uphill between T5 & T6 where the sound tower is. Good luck, it's a *****.
    As far as a datapoint -- my car 2.2 liter 4 cylinder requires an 10" muffler to get to 90db.
     
  4. FLATOUTRACING

    FLATOUTRACING F1 Rookie

    Aug 20, 2001
    2,684
    East Coast
    Full Name:
    Jon K.
    Rob,

    Every Challenge kit for the 355 came with a loud exhaust and a quiet muffled one. If you only have one exhaust it's likely the loud one which will peg the sound meter at anywhere from 106-112 db's depending on where the noise meter is and what rpm you're in when you pass it.

    The quiet muffled exaust came in at around 102 to 103 (SCCA and many track specific).

    FYI: if you don't have the quiet exhaust locating one will be next to impossible. The factory doesn't have them and if you can find a dealer that has one lying around it'll cost you at least $2000-$2500 at a minimum.

    You're likely going to have to come up with an aftermarket/home made solution.

    Regards,

    Jon P. Kofod
    www.flatoutracing.net (new site)
     
  5. redhead

    redhead F1 Rookie
    Consultant

    Dec 26, 2001
    4,869
    Full Name:
    ~Red~
    Rob,
    I have been to MANY open track events at LS. What the most common solution is, to simply lift or short shift. My experince in a F355 with Tubi and no cats was to shift into sixth, and lug it, and then after the bridge, downshift in for turn 6. I have seen, as Hubert stated, baffles, and directional exhaust, to exit on the Driver side, as the tower is on the exit of 5, up the hill.

    Hope this helps.

    Rich
     
  6. beast

    beast F1 Veteran

    May 31, 2003
    8,965
    Lewisville, TX
    Full Name:
    Rob Guess
    Rob,

    Are you goint to need at pit help for the historics race???? If so just let me know :)

    Rob
     
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  8. rob lay

    rob lay Administrator
    Staff Member Admin Social Subscribed Miami 2018 Owner

    Dec 1, 2000
    51,475
    Southlake, TX
    Full Name:
    Rob Lay
    well, I'm not sure what is going on. I know I'm doing the FCA track day Wednesday and Thursday.
     
  9. rob lay

    rob lay Administrator
    Staff Member Admin Social Subscribed Miami 2018 Owner

    Dec 1, 2000
    51,475
    Southlake, TX
    Full Name:
    Rob Lay
    I know FNA has talked about it in the past, but you haven't heard of them having race groups for the 348 or 355 Challenges?
     
  10. fatbillybob

    fatbillybob F1 World Champ
    Consultant Owner

    Aug 10, 2002
    19,797
    socal
    I may be helping to tech cars for FCA at LS. I asked LS and they say the sound mike is 50ft from the track. This is important because sound DB falls off with distance. You can get a close guess as to how loud you run with a radioshack DB meter that cost less than $40. I do know that in my garage 3 feet from the tailpipe I was at 90db with testpipes and challenge exhaust on a 348. I am running LS this weekend and will be there with a single can modified 348 exhaust to make the noise limits. For your 355 it is very easy to just weld up some pipes. I do this all the time. BTW the 348 is much quieter with the challenge exhaust and cats. So if you have cats in it will make a difference. I have never been allowed to run LS at over 92db. FCA got a 103db limit
     

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