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Tips For Quietening Exhaust Down (Re. Track Days)

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Tips For Quietening Exhaust Down (Re. Track Days)

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Old 10 July 2007, 10:56 AM
  #1  
tonybooth
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Default Tips For Quietening Exhaust Down (Re. Track Days)

The last time my car was tested it was 105db static, but this was before de-cat down pipe was fitted.

Car is a 94 Type RA running a full HKS 3" system. Is there a quick and easy way to reduce noise to comply with limits imposed at certain tracks?

Cheers

T
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Old 10 July 2007, 11:12 AM
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JohnD
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One could say that if it's too noisy for the track, it's certainly too noisy for the public road? Seems somewhat perverse that you need to make the car quieter to go on a race track?
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Old 10 July 2007, 11:30 AM
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tonybooth
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Originally Posted by JohnD View Post
One could say that if it's too noisy for the track, it's certainly too noisy for the public road? Seems somewhat perverse that you need to make the car quieter to go on a race track?
JohnD
I am sure it is too noisy for public roads, but as it is not road registered I don't really care

T
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Old 10 July 2007, 11:46 AM
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Merlin motorsports sell universal silencers that attach to the exhaust tip for this very job. I have one thats surpluss to requirements and has never been used (my old Westfield was borderline and it squeezed through the scrutineers so I never used it)

I bought it for a 3" exhaust so it might fit, if you want to go this route PM me
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Old 10 July 2007, 12:27 PM
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funkyspider
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http://www.scoobyworld.co.uk/catalog...oducts_id=1294

There's a bung available on here, scroll down slightly.
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Old 10 July 2007, 12:49 PM
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D1CCY
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Drill a couple of holes near the end of the tail pipe and fit a 1/2" bar across the tail pipe. Will quieten it down quite a bit. Did this on a mate's car and SPL dropped from 102 to 99 dBA.
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Old 10 July 2007, 01:27 PM
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A silencer (even straight through) in the centre section makes a heck of a difference as well, especially on unequal header 'burble' cars.

Simon
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Old 10 July 2007, 01:32 PM
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What someone suggested to me was to change th back box for one which is made of a material that is less likely to resonatate as much i.e titinium back box.

Would this make a difference for noise level testing at track days ...?
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Old 10 July 2007, 04:22 PM
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tonybooth
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Thanks for the replies

Just looking for a quick fix to dampen the noise if I get pulled up - Not happened so far, but it will if I go to Donnington

The Scoobyworld baffle could be the way to go as I am sure pipe is about 4.5"

Cheers

T
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