Track day noise

[bertie]

A while ago I got chucked off Donnington in my totaly standard R400 for noise.

 

Limit is 98dB and I was measured at 101!!

 

I've since fitted a Raceco silencer and a Reverie carbon airbox but I still reckon it might be marginal.

 

I was thinking of making the exhaust rear exit but I'd love to know how others with R300/400/500s go on and what you've had to do.

 

Cheers

[CageyH]

After a Raceco and reverie airbox, you should be fine.

Just make sure the can is well packed.

 

Only dead fish go with the flow....!

[Stationary M25 Traveller]

Noticed yesterday that my electric hedge trimmer is labelled 105db.

 

Guess that wouldn't be allowed either !

 

Wonder how they trim the hedges at Goodwood ?

 

******************

And you run and you run to catch up with the sun, but it's sinking...

 

And racing around to come up behind you again. Seven related photos

[peterg]

Ah but is that at 1/2 metre at 3/4 revs 😬

[bertie]

Donnington is 98dB drive by and there are 4 meters round the track direclt linked to the local authority!!!

 

Obviously as the man was chucking me off I couldn't hear him so we had to pause while the jumbo landed at East Mids airport!!!

[Jason Plato]

There is only 1 mic , what if the tailpipe pointed skywards?

[sjmmarsh]

.... or points under the car

 

Steve

[bertie]

Donnington used to have only one mic just before the start gantry.

 

As I said earlier, now they have 4 around the track.

[Jason Plato]

have you seen the other mics 🤔

 

here is C7 TOP

Taffia rear gunner

 

[Grubbster]

They always talk of other mics but according to my (usually reliable) source they still have just the one. Sadly I think I have to give up on Donington for trackdays now as I seem to get blackflagged far to readily no matter what I do ☹️

[Nick Chan]

Bertie,

 

Any idea of what your car now registers on the meter with the Raceco and Reverie airbox? I am keen to make my R400 quieter for road and track use. Is your setup a lot quieter than before?

 

Nick

 

The BEC has gone - now onto an R400!!

[Tigger]

I was at Donny last week and had a problem with noise 99.3, in the end I fitted a rather smart external baffle (a Coke can) and with a bit of light footed acceleration just after the chicane all was well. I'm pretty certain that they only operate a single point monitoring, elsewhere I was going full chat :)

 

I do find the noise limit a bit daft at Donington since it's right under the flight path of East Midlands Airport

 

Tim

 

[FTH]

Surely its possible to fabricate a "Db eater" Akrapovic style?

Which basically consists of inserting into the end of the exhaust pipe a smaller diameter metal pipe, with an OD slightyly smaller than the ID of the exhaust pipe.

[Bobo W]

I've got a merlin muffler which does a good job although I just need to remember that the muffler sticks out 6 inches or so from the car so am careful going for those small gaps.

[Ben C]

Hi All,

 

I have a very loud VX 2.0. It’s normally the nosiest car on the track. Yesterday I was pulled up at Brands.

 

The marshals said that I had to have another test which it passed at 5000rpm. I explained that the majority of the noise was intake and that I had a mod I could try.

 

It consists of a piece of ABS plastic sheet bent up to cover the air filter (a pipercross). It has a 90deg bend which clamps between the bonnet and the side panel, a horizontal top which I duck taped to the bonnet above the air filter. The vertical face against the filter has hairy sound deadening matt (1/2" thick) glued to it. It is open at both ends to let the air through.

 

Ok it does not look pretty but is easily fitted / removed, stayed in place at 110 mph and produced a drive by figure according to the marshals of 88db. They were very impressed! I could not notice any drop in performance.

 

If anyone wants further info drop me an email and I will take some photos to send you.

 

Ben

 

ben.cutting@seabrookstransport.com

 

 

[caterhamnut]

Ben - you're damn lucky its ABS you are using and not our 'motorsport composite', otherwise our lawyers would be onto you!

 

here

for our complete range!

 

😬 - ah - those were the days.

 

Regardless of material (although obviously ours is best) this does work for intakes!

 

Mark (355GTS) is getting a rear box made up for his rather loud VX to enable him to do more tracks next year (as opposed to airfields)

 

www.mycaterham.com

here

Videos

here

101,000 miles car

 

Edited by - angus&tessa on 3 Nov 2007 00:24:46

[pezzer]

If it helps my standard R300 with cat was measuered at Cadwell last week at 98dB. I'm not surprised that an R400 is over the limit. I worry about not being allowed on regularly.