Exhaust Options to comply with trackday noise restrictions

[Andy-Runner]

Recently i have noticed a few people buying exhausts and finding they are not suitable for track use and having to re-sell etc , therefore i thought it would be a useful thread to post up stating which exhausts people have successfully used on circuits without getting thrown off and (briefly) any other additional mods which would impact the noise level i.e. decat pipes etc.


I'll start off:

1. BERK TECHNOLOGY + DECAT - DONINGTON PARK

[skinthespin]

2. HKS Super Drager with and without de-cat - Donington quiet day - 98db
3. XS Power Twin exit exhaust with XS power DP (Which I was amazed at!) - Donington quiet day - 98db

Used these at other tracks too but Donington was the quietest.

[lockys96]

i feel a custom hay & scott custom one,

or designed to be track legal.

[jonb-]

Departure 2 pro + decat - Donington, Rockingham, Silverstone. Bedford is the crunch circuit as they're the strictest.

[2Crooky]

Departure 2 pro + decat - Donington, Rockingham, Silverstone. Bedford is the crunch circuit as they're the strictest.

On a stock turbo.....but anything larger and noise levels get pretty high with this exhaust.

[Andy-Runner]

What about an Apexi GT (with the baffle included?) A friend of mine wants to take his tubby on track for the first time this year and he has one of these exhausts along with a de-cat

[jonb-]

What about an Apexi GT (with the baffle included?) A friend of mine wants to take his tubby on track for the first time this year and he has one of these exhausts along with a de-cat

Where?

Most places fine. Bedford i'd get a free test.

[Andy-Runner]

He wanted to try donnington (with me on the 17th May) and then silverstone mid summer.

Thanks for the reply Jon

[jonb-]

I wouldn't worry about Donny, if Skins car is allowed anything with a baffle will be fine.

I'll book the 17th on the condition you let me use a set of your 16s with road tyres for a session

[Andy-Runner]

can't see there being a problem mate - i'll pm you later

[Icsunonove]

Bedford is the crunch circuit as they're the strictest.

Yes it is. Just to clarify the limits are:

The noise limits at Bedford Autodrome will remain unchanged at 101dB(A) static (measured
0.5m from the exhaust at a 45’ angle at ¾ maximum revs) and 87.5 dB(A) drive-by at 20
metres.

[jonb-]

Bedford is the crunch circuit as they're the strictest.

Yes it is. Just to clarify the limits are:

The noise limits at Bedford Autodrome will remain unchanged at 101dB(A) static (measured
0.5m from the exhaust at a 45’ angle at ¾ maximum revs) and 87.5 dB(A) drive-by at 20
metres.

Just to clarify your clarification they don't usually measure static so don't think if you pass that you're fine, it's the drive by that gets you and that can only really be tested at their circuit and even then varies from day to day depending on atmospherics.

[draz1k]

anyone running with a nur spec and larger turbo got a reading? i still have my bung to stick in , but sure it will still fail

[GTSMick]

I could really do with knowing wether a NUR SPEC and decat would pass sound regs too - i hope to do some trackdays this year and i am running this setup at the moment too

Suppose i could always use the bung............... for the first time!

Didn't Mike's car have a NUR on it for the Time attack series - or are regs different for this?

[jonb-]

Didn't Mike's car have a NUR on it for the Time attack series - or are regs different for this?

Timeattacks were run on "race" (noisy) days so no sound limits enforced.

[Andy-Runner]

NUR spec

Not sure about that one mate - i would imagine you would be ok if you used the bung (if you have it?)