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Laquna Seca Noise Question

Discussion in 'California & Nevada (Northern)' started by LouB, Jul 24, 2004.

  1. LouB

    LouB Formula 3

    Apr 15, 2001
    1,811
    FL, OR
    Planning on bringiing my 360 spider with TUBI to the FCA National Meet and am worried about meeting the 103 db noise level between turn 5 & 6. Any one have direct experience with this combo?

    I guess I can always slow down and upshift in that area-right? Do Challange cars run this track without problems?

    Would not like to be black flagged after shipping the car across country just for this event!
     
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  3. 4i2fly

    4i2fly Formula 3

    Apr 16, 2004
    1,330
    SF, Bay Area
    360 with Tubi should not be a problem. I think the loudest 360 with Tubi belongs to my buddy and he got black flagged twice in the same day at Laguna doing 97 and 96db. I have a Tubi in mine and is not as loud as his...

    By the way they usually give you three warnings before they sideline you for the day.
     
  4. cmparrenzo

    cmparrenzo F1 Rookie
    Rossa Subscribed

    Mar 3, 2002
    2,685
    Kansas
    Full Name:
    Chris Parr
    Your 360 will be fine.... My F40 has straight pipes, no cats or mufflers so I have to use the "girlyman" california exhaust to put on for track time..... silly huh? Comp exhaust for the street, street exhaust for the track!

    Chris
     
  5. Rifledriver

    Rifledriver Two Time F1 World Champ

    Apr 29, 2004
    26,951
    Austin TX
    Full Name:
    Brian Crall
    As the assistant tech chairman for the event, I am sorry but I cannot provide you with an answer to your particular combination. I will say, I strongly advise you to get a sound meter and test it yourself. You have to understand that the people monitoring the the sound measuring equipment do not work for us, or in our interests. They work for the people of the community that have been complaining about the noise levels from the race track. And while I agree that moving into, or building a house next to a racetrack (if you don't like the noise) is about as stupid as it gets, we all know how much good that argument is when it comes to an airport whose importance to a community is unquestioned. Yes, you will get a warning, but it won't do you any good if you are not prepared or equipped to make your car quieter.
     
  6. bobafett

    bobafett F1 Veteran

    Sep 28, 2002
    9,193
    Chris: it's ridiculous.

    Brian: you described it perfectly. Absolute stupidity, imo, on the part of the occupants. By the way, I met a friend of yours yesterday: Dale D.

    --Dan
     
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  8. twatson

    twatson Karting

    Feb 3, 2004
    70
    Sound at Laguna is always a problem for some one. It is not only exhaust noise but other engine and drive train noise that can create problems. I have a Porsche 962 that I have run there in the past on vintage days and it will sometimes get into the 106 db range and I am sure that the exhaust sound is not the issue as the car is quieter than the CanAm cars which don't seem to have a problem. It also depends on the time of day and the weather. For SCCA events the louder cars run mid day. They (SCCA and the County both) monitor the sound from about 50 ft from the edge of the track on the outside just before the bridge and turn six (look for the little glass shack), but if you run on the inside of the track the sound bounces of the cement wall and everyone passes you. On trick that I use on my atlantic car is to put a 90 degree tip on the end of the exhaust and turn it away from the sound meter and at about a 45 degree from the ground. Since sound looses db from every surface it bounces off of (in this case both the asphalt and the inner cement wall), that is usually enough to get me under the legal limit on race day. A muffler shop can make these pretty cheap but may scratch up your nice exhaust pipe tips. You might want to get a couple and bring them just in case but I doubt your car will be a problem. I have the tubi's on the 550 and it is really just a little more noisey at the low rpm range but like the stock at the higher range that you will be driving at on the track.

    Sometimes they will let you take a sound run between sessions to test your car if you are worried and then you can let it all hang out in front of the meter to see if you have a problem. The your own sound meter idea may be a good idea if you are worried and you can get a cheap one at Radio Shack and then use it on your home theater system as well when you are done. Set it up 50 ft away and let your car rev up and drive by the meter (that way you will get all the noise from your car). Letting of the gas up the hill between turn five and six is a real drag and takes alot of fun out of driving Laguna (been there, done that).

    Sound is always an issue at Laguna except on the 5 or so days when they run the pro events and is one of my pet peeves about running there.
     
  9. 4pipes

    4pipes Rookie

    Jul 12, 2004
    4
    saratoga, CA
    Full Name:
    Dave
    I was black flagged at an FCA event when we ran a 90dB limit. I have a 550 with Tubi's. Since every dB is a doubling of sound pressure, I think I'll be alright at 103dB noise limit......that is really loud.
     
  10. Rifledriver

    Rifledriver Two Time F1 World Champ

    Apr 29, 2004
    26,951
    Austin TX
    Full Name:
    Brian Crall

    FYI, A STOCK 360 exceedes that limit.
     
  11. Brian C. Stradale

    Brian C. Stradale F1 Rookie
    Lifetime Rossa

    Mar 17, 2002
    3,603
    Dallas, TX, USA
    Actually, every 10dB is a doubling of the sound level.
    So, 100dB is twice as loud as 90db... a huge difference.
    103dB is 50% louder yet.
     
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  13. Gary(SF)

    Gary(SF) F1 Rookie

    Oct 13, 2003
    3,637
    Los Altos Hills, CA
    Full Name:
    Gary B.
    Brian -

    Just another data point...I have a Capristo level-2 360 and had no problem on a 92dB day.

    Gary
     
  14. sinbon

    sinbon Karting

    May 16, 2004
    78
    Petaluma, CA/SLO,CA
    Full Name:
    Bobby Boinski
    correct.
     

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