Noise Checks before Castle Combe

[MichaelH]

Now that Kevin has organised the track day at Castle Combe with a noise level of 100dba (lower than most circuits)

 

I would rather get my car checked locally before I plan to go. It is 280 mile round trip and even if I get my entry back if the car is too noisy it would be v frustrating and the problem could be sorted out ahead of time.

 

So the question is - how can I get my car checked for noise locally?

 

Thanks for your applied knowledge

 

Michael

Edited February 18, 2014 by MichaelH

[roy53]

merlin motorsport parts are located in the circuit and have many items to help reduce the noise level, Something that has always been a problem at this circuit.

 

ROY

[MichaelH]

I am think locally to me rather than go all the way down there

Michael

[Motorsport Mickey]

Hi Michael,

 

Check out the Blue Book, there should be RAC approved scrutinisers listed in there, (was when I did it). I trailered my car down to Leicester and he did a noise test whilst it was on the trailer which he was quite happy with ( I did offer to take it off) checking it from different angles, he did make a small charge. If they aren't listed in the Blue Book give the RAC a bell and ask for a local man.

 

regards Mick

[TRTOM2498PI]

Hi Michael,

 

PD Gough in Nottingham (a stainless steel exhaust custom manufacturer). They have a noise tester, and can design an accessory that can be slid onto the end of yoru tail pipe, to reduce noise.

 

They made me a piece up for my MK1 Golf 2 litre 16v whilst I waited, and it worked. Not too expensive, either.

 

PD Gough & Co. Ltd.,
The Old Foundry,
Common Lane,
Watnall,
Nottingham,
NG16 1HD

By Telephone:
+44 (0)115 938 2241

By Fax:
+44 (0)115 945 9162

By Email:
info@pdgough.com

 

 

Cheers.

Edited February 18, 2014 by TRTOM2498PI

[Motorsport Mickey]

Hi Tom,

 

I'd checked my noise with the works decibel tester before trying the RAC man and got the same result as his numbers, however if the RAC man had gotten different figures I know which figures I'd have tried to comply with ! You can't argue with them.

 

Mick Richards

[Guest ntc]

Is there not an App for that?

[Alec Pringle]

Combe is our local circuit.

 

The problem is a group of miserable bastards who moved into the area because it's a pretty village, and then got together to close the circuit that had been there for half a century before they turned up. The sort of folks who should have been strangled at birth.

 

Net result, the circuit operators have to be VERY stringent, and they WILL err on the cautious side.

 

I would have the car noise checked by an RAC scrutineer, and make sure it is well inside the limit, not marginal.

 

Our road V8 would need the exhaust system replacing to go on track, which cans that for an idea. Too expensive a day out.

 

Cheers

 

Alec

[alan57]

Michael,

As a temporary,emergency measure, you could fit an item called a "Supertrap" which simply fits on to your tailpipe. Probably available from Merlin at the circuit, or from DT(etc) in advance. Will kill some power and make your car sound like a wet fart, but useful for an emergency. But wise to have the car sound checked as suggested - you might be pleasantly surprised (XXD is usually well under 100 on a static test!) - but beware - I think CC sound checks are on a drive by basis, and not necessarily static - can make a difference!

Edited February 18, 2014 by alan57

[MichaelH]

I am glad to hear that Alec is his usual broad minded and liberal self. The local noise objections are something that we will have to learn to live with or take up darts.

 

For my money cars can all be reasonably quiet, that includes race and rally cars. Having done some road rallying there is nothing so nice as to have the locals wave you on rather than shake a fist at you!

 

Michael

[MadMarx]

Bought today a sound level meter for 50€.

First test: My shouting did reach a level of 101.9dBA with a distance of 20cm and fast measure mode.

 

You could get one yourself.

I also wanted to measure the noise level of enragement of my wife.

When I told her about the IMSA TR8 coming she had been more loud than me.

A case for emission control law :-)

Too late to measure that, already done now.

Funny how wife adjust quickly to new situations and telling everybody her husband bought another race car.

Women - funny folks.

[kevin bryant]

I've just checked my paperwork and it says "100dba measured at 0.5 metres from the exhaust pipe at 75% of maximum revs".

 

But on the topic of the importance of noise in motorsport, I've seen the super fast but virtually silent Audi at Le Mans (boring) and the much slower but noisy V8 Corvettes (wonderful). Give me a grid of Corvettes any day of the week.

 

take care (but sign up for the track day)

Kev

[Guest ntc]

Kev

Turn the sound up

[Alec Pringle]

Hi Michael,

 

the Castle Combe noise question invariably makes me feel particularly broad minded and liberal.

 

A handful of incomers to the village of Yatton Keynell were, and those few that remain still are, the problem. Funnily enough, the council leader represents the village as councillor, and is a local too . . . . so the protestors were lucky enough to have the council functionaries on the case, as it were. Always a benefit having a council leader involved, I reckon. Concentrates the minds of local government officials wonderfully.

 

The large number of folks signing petitions, writing letters etc etc in support of the circuit counted for naught against a handful of villagers. Well there's a surprise. Democracy in action, not what you know but who you know, it isn't really a numbers game after all.

 

The costs of court action almost shut down the circuit. As it was, the circuit survived by a whisker, but on a much reduced basis.

 

Those who'd bought residential property cheaply, when it was affected by circuit noise, then protested about the circuit that had been there for half a century, pocketed the profit on resale and cleared off into the sunset.

 

Us West Country motor sport enthusiasts have a much reduced facility as a result.

 

The Conservative council leader in question made the headlines a couple of months back, rattling the Conservative government's cage with a 22% increase in expenses allowance for leading Wiltshire Council, in a year when most of the county's population including council employees had seen sod all in rises. Democracy in action, to those who have . . . . etc etc.

 

As I was saying earlier about misery and strangulation . . . .

 

Cheers

 

Alec

[kevin bryant]

Neil,

 

Floats my boat. Proper grunt. I love it.

 

(Sign up) Kev

[JRCWeedon]

I am glad to hear that Alec is his usual broad minded and liberal self. The local noise objections are something that we will have to learn to live with or take up darts.

 

For my money cars can all be reasonably quiet, that includes race and rally cars. Having done some road rallying there is nothing so nice as to have the locals wave you on rather than shake a fist at you!

 

Michael

Much as it irritates noise levels are a problem if you compete anywhere but particularly at some circuits - Goodwood and Castle Combe spring to mind.

Our cars generally can be made to comply and the Merlin Shop has quite a selection. They sell "cans" of various diameters which can go on the end of the pipe assuming you do not have a rolled edge - last time I enquired about £50.

Me I have an extra silencer across the back of the car which seems to do the trick.

Regards

John

[MikeHughes]

Alan is correct Castle Combe certainly used to be one of the few UK circuits that operated a drive-by noise test as opposed to a static test.

 

I remember a TR Register race at Castle Combe in the late 1980's. Pete Cox had qualified his modified TR4 on the front row but had fallen foul of the drive-by noise test and was required to rectify it for the race. He went to Merlin and purchased a Supertrap. It zapped the power so much that he spent the entire race dicing with the leader of the Roadsports class in the lower midfield!. He was not happy.

 

The benefit of the static test is that when you roll up to be tested the scrutineer will ask you what maximum revs you use. This is where you can be a little liberal with the truth! I have a particular noisy spot at 4500rpm on my TR5 so try and avoid that point especially if I have my noisy silencer on the car. If I have my quieter silencer on there is never a problem.

 

Mike

[kevin bryant]

Well I've no idea why they have moved from a drive by to a static test, but our contract with them says it's a static test the cars must pass. There is no mention of drive past testing. I guess they can re-test and re-test any car they feel may be close to or over the limit.

 

Take care, and please sign up

 

Kev

[Dave McDonald]

The benefit of the static test is that when you roll up to be tested the scrutineer will ask you what maximum revs you use. This is where you can be a little liberal with the truth! I have a particular noisy spot at 4500rpm on my TR5 so try and avoid that point especially if I have my noisy silencer on the car. If I have my quieter silencer on there is never a problem.

 

Mike

 

Mike

"...a little liberal with the truth!" Surely not, you a Paragon of virtue in the Paddock. Fancy you misleading those well meaning people for all this time.

And juggling silencers to best benefit yourself as well. Tut, tut, I see you in a new light now.

And to think that you were that guardian of the Championship Regs for so long, berating we drivers for the most minor of indiscretions.

Dave McD

[Alec Pringle]

The circuit operators are in a peculiarly difficult and unenviable position, given the resources of the small minority of local protestors. There is no option but to rigorously enforce the letter of the agreements with the council in respect of noise monitoring. That requires a static test before ever letting cars out on the track.

 

Bear in mind that most of the protest comes from properties beyond the opposite side of the circuit from the paddock.

 

It is logical that there should also be a drive-by metering facility on the track at the point closest to the protesting residents - some of whom have in the past had no hesitation in spending many hundreds of pounds on professional noise recording equipment.

 

I would assume that the Triumph event will follow the norm, static measuring initially, and then subject to drive-by monitoring.

 

The static noise test figure for cars at Castle Combe is measured at 4500rpm specifically, it is NOT taken at 3/4 of maximum rpm . . . . except, and only except, in the case of motorcycle engine cars, which are measured at 3/4 of maximum rpm.

 

As an aside, the 4500rpm figure was supposedly determined long ago by MSA on the grounds that a very substantial majority of engines demonstrate a particularly loud exhaust noise peak at or around 4500rpm, regardless of number of cylinders and of whether their maximum rpm is 5000, 7000 or 10000. The subjective character of that peak is evidently also louder than its objective measurement.

 

Cheers

 

Alec

[kevin bryant]

Alec

 

I've checked the contract again and it says three quarters. Of course that could a lack of communication between those that actually do the job and those in the office.

 

On my visit, prior to booking, the chap did explain that it wasn't those nearest the track that objected but rather those from a village some distance away, as you say beyond the opposite side of the circuit from the paddock. He did reassure me though that the team at Castle Combe worked with the driver and Merlin Motorsports to ensure that everyone can get through the noise test.

 

take care

 

Kev

 

PS I've 11 bookings at the moment so we're about 20% there on our target of about 50 cars. Please don't leave it to the last moment to book. It'll give me sleepless nights worrying about the potential losses.

[rcmcewen]

Hi Alec,

I regret that your advice is incorrect.

The noise test is carried at at 75% maximum revs as per the Blue Book for race tracks. Normally for Sprints and Hillclimbs it is at 66% maximum.

I doubt that many people will have any problem with the noise test unless their car is unsociably noisy.

Merlin do a good range of easy to attach noise limiters, their shop is at the circuit.

Regards

Roger McEwen

[Alec Pringle]

Thanks Roger for the confirmation,

 

I was indeed under the impression that the noise test is still carried out for sprints as it is for races at Castle Combe, ie 3/4 rpm at 0.5m. Evidently that is the case.

 

Presumably the same noise test procedure would apply for test or practice days (which may involve at least a limited opportunity for timing), ie that they should be treated as race or sprint events for the purpose of safety and/or technical regulations ?

 

Whereas, for both action days and track days (where timing of any form is specifically prohibited), at Castle Combe the procedure has been

 

"All vehicles using Castle Combe Circuit are sound tested. The limits are enforced throughout the day and are set at 100d(b)A measured at 4500rpm on a static test with the sound meter set at 0.5m from the exhaust outlet."

 

That procedure is still shown as in place on the Combe website for both action and track day regulations, so I presume will obtain for 2014.

 

I had assumed that the Triumph day would be following the traditional Castle Combe track day (as opposed to sprint) format, and therefore utilise the usual noise test. Evidently that is not the case.

 

No big deal either way, except for those cars which produce a different noise level at 4500rpm and at 3/4 of maximum rpm.

 

The three quarter figure is just 3750 on a standard wet liner 4, but might be 5500+ on a modified 4, 6 or 8 banger. From past experience, that margin is more than sufficient to tip the balance on a circuit with a tight noise measurement regime - old lags will recall the occasional shenanigans at TR Goodwood sprints of many years ago.

 

The last thing that's required is to be returning some disappointed enthusiast's entry fee.

 

The Merlin service is very good, always has been, but there's invariably a performance penalty from stuffing on a temporary extra silencer, and a need for some modest retweaking. Spoils the day if an effectively leaned mixture or retarded timing cooks something . . . . Much preferable to sort the car in advance.

 

Cheers

 

Alec

[jellison]

How many race cars do you need Chris!

[TRTOM2498PI]

Bring your 6. !