Classic 2CV Racing Club

Classic 2CV Racing Club Ltd Forum => Technical => Topic started by: philip myatt on April 04, 2011, 13:39:46

Title: Car noise testing
Post by: philip myatt on April 04, 2011, 13:39:46
Volunteers required.
Croft has very strict noise limits placed on it by the local council, in our efforts to find an alternative venue for the 24hr (our date at Snetterton is under threat) we need to see if we can be quiet enough to be compliant.
To help move things forward I have organised a days noise testing at Croft on 2nd June. Due to the noise restrictions we may be only able to run for 15mins in every 30min but it is very important for us to gather data and try to understand the implications of how much noise we make.
We need to have a number of cars running on the circuit so that we can monitor the noise both trackside and in the local village.
The day itself will be FOC but anyone running will have to make modifications to the exhaust system to meet our new requirements. (Possibly 88dB or lower).
I intend to run my car at Silverstone with the new proposed system on it so that everyone can see what may be required for our race at Croft this year. We envisage that this will at least require an additional silencer fitted across the back of the car, under the boot, exiting on the drivers side (RHD), so that it is pointing away from the noise meter at Sunny Out.

Anyone interested in some free testing and helping the club at the same time?

Let me know

Philip
Title: Re: Car noise testing
Post by: Paul Robertson on April 04, 2011, 14:21:40
we will bring sammies and tony's cars phil.
Title: Re: Car noise testing
Post by: Derek Coghill on April 04, 2011, 18:21:36
Will have a check end see how that fits; I already have a rear-exit exhaust (I did ask for a figure the last time it was tested but I can't remember what it was - significantly quieter than average though). The worst thing about it is resonance!
Title: Re: Car noise testing
Post by: Simon Crook on April 04, 2011, 19:49:27
 :o :o :o how under threat is it - would love to come along to Croft but still out of the country (sorry) when the exhaust system is done and if we go along this route can we please have lots of pictures of said exhaust put on the forum
Title: Re: Car noise testing
Post by: Mary Lindsay on April 05, 2011, 16:44:07
I am very concerned to hear that our date at Snetterton is under threat. What is the problem? Is it cost or aren't we up-market enough for their new image?
Title: Re: Car noise testing
Post by: Matthew Hollis on April 05, 2011, 21:01:58
Don't worry, it is completely safe for this year (or was at the AGM).  Mr Palmer has been quoted as saying he would prefer a different type of car racing on his new long track, but it is just speculation at this point.  The club is simply investigating other possibilities should we not be welcomed back to Snetterton in 2012.
Title: Re: Car noise testing
Post by: philip myatt on April 06, 2011, 09:08:30
Jonathan has open stated that whilst 2CV's are fun they are not high enough profile for his circuit. He is actively pursuing alternatives for 2012, these may however come to nothing and our date will be safe.
We then have the issue of circuit costs, we were initially led to believe that it was no problem for our race this year to be on the 300 circuit, they have now come back to us to confirm that it will be OK as long as we pay an extra £10000.
Should Croft be a viable alternative it will cost 10's of 1000's less to hire which will then be reflected in the entry fee. We have to work very hard to ensure that we can comply with the requirements to run there.
There are a lot of if's, but if we lose our Snett date we at least need a backup at an UK circuit unless you are all happy for our annual 24hr to be held at Spa (which can be easily arranged).
Not surprisingly there are not many options to choose from, does the circuit have planning permission to start with, can we compete with Britcar, could we afford Silverstone, Donington or??? even if it was feasibly possible to hold the event at that circuit, our options are very limited.
Title: Re: Car noise testing
Post by: Derek Coghill on April 07, 2011, 15:40:34
Phil, I thought Croft were restricted as to how much racing they could have? Or is that restriction dependent on the noise levels?
Title: Re: Car noise testing
Post by: philip myatt on April 08, 2011, 08:30:13
They have quite a complicated agreement that restricts the on track usage, basically they are restricted to numbers of days at differing noise levels. The noise is measured as an average over 30mins with a defined peak level permitted, this creates a Leq ave figure. On a quiet day there aren't even standard road cars that can run non stop without exceeding the limits.
It is not possible without some reliable data to accurately predict what dB we need to specify for each individual car to ensure that we are compliant with the 30min ave when 30 cars are on the circuit. The more cars we can put out on the test day will increase the accuracy of the calcuations.
Thankyou to those who have already volunteered, but a few more would be a big help. Would a free silencer help anyone with their decision?
Everyone will have to run to this new spec in July as its the only way we can confirm what our actual noise level is. The quieter we can be the better. We will issue a dB level for each individual car as soon after the test day as possible.
Title: Re: Car noise testing
Post by: Nick Grant on April 30, 2011, 22:56:45
Phil,

Does the July date mean modified exhausts required for Anglesey or just the Croft race.

Thanks.

Nick.
Title: Re: Car noise testing
Post by: philip myatt on May 01, 2011, 09:20:10
They will only be required for Croft at present.
Title: Re: Car noise testing
Post by: philip myatt on June 03, 2011, 09:05:44
Hi all.
Many thanks to the 10 car/driver combo's that turned up for the noise testing yesterday. I can report that it went very well, exceeding all our expectations.
All cars were fitted with twin silencer exhaust systems with the exit on the offside rear. The noise range produced was 83-87db at a static test. To bring this
programme to a conclusion it will now be a mandatory requirement for all cars to comply for all our races at the Croft race meeting this year. If you need
help or advice with this just ask.

Philip
Title: Re: Car noise testing
Post by: Simon Crook on June 04, 2011, 09:46:38
Did anyone get any pictures of the exhaust?
Title: Re: Car noise testing
Post by: Paul Robertson on June 04, 2011, 20:47:20
i will send you some simon
Title: Re: Car noise testing
Post by: Simon Crook on June 05, 2011, 11:13:17
thanks Paul
Title: Re: Car noise testing
Post by: Chris Yates on June 06, 2011, 10:15:38
Can I have some too? :)
Title: Re: Car noise testing
Post by: Mary Lindsay on June 06, 2011, 11:52:22
I would like some too, maybe it would be an idea to put them up on the web site?