Noise at Bedford.

[jbaddeley]

About to do my first track day at Bedford and have noticed that their noise limits seem quite low. Not sure how noisy mine is when being driven hard, how can I check or can anyone advise me where the sound meters are. I'm confident that the car is quite enough on idle. Cheers. JB

[DocJock]

You realy don't want to be cheating the drive-by meters.

There was a huge bust-up at an SIDC trackday there a couple of years ago with people sent home and quite a few banned from the venue in an argument over noise.

[yanmar]

they check you at the gate when you arrive.on mse track day i was 94, at bedford 98+abit only just allowed. its worth geting in as its a great track, enjoy

[mko9]

As said above, they check you at the door at Bedford. A bloke with a sound meter measures at .5m and 45deg off from your tailpipe while you hold 4500rpm. If you post up your ride and mods, perhaps someone else can give you an idea of whether it will pass.

Not knowing what you are driving, I passed by 2dB in a mostly unmodified Skyline GT-R with a decat exhaust.

[hammerwerfer]

And I thought this thread was about Joe911's mount.

[batman69]

From your profile you are driving a clio (front engine always a benefit for static test) it just depends how much of a drainpipe your exhaust is, most unmodded road cars pass easily, so would be suprised if you failed the static @4.500rpm.

Hints on passing static - 1)make sure car is well warmed (noisier when cold), 2) depress clutch so there is no driveline/gearbox chatter 3)increase the revs slowly as any slight over rev can peak the sound significantly.

Usually at bedford if you trip the drive-by then they pull you in for a quiet word in your shell-like. The mics for the drive-bys are all at points on the circuit where you are giving full beans so if you learn where they are you can short shift/move away from mic (Distance & Wind are your friends, if you are noisy these help dissipate noise faster)

Unless you are very loud on the road, you'll be fine.

[zumbruk]

A mate's 5.2 TVR Griffith sailed through, so a Clio's going to be no problem at all.

[jbaddeley]

Thanks for the advice. My clio has a performance exhaust, schrick cams, induction work and was fine at Donnington where there limit was 98db. The cat is still in place so this helps. However, my concerns were raised when i looked in the UK circuit guide which says the drive by db is 87.5 and static 101.5. I've since noticed that Easytrack are saying the limit is 99db so hopefully will be ok. Still not sure whether this is static figure or drive by.

[shnozz]

either way, if your Clio passed at Donington, you should be ok. Mine is around 96 and Donington and Bedford have not been an issue.

[DocJock]

A friend's bog standard M3CSL failed the drive-bys at Bedford so don't assume standard is always ok.

It also seems that certain frequencies are more likely to trip the meters. I've seen cars which subjectively seem very loud pass whilst seemingly 'quieter' cars fail.

[shim]

i had been to bedford 3 times in stock M3CSL and no noise issues at all on static or driveby test.

[batman69]

If you did Donny you'll be fine. I believe the drive by at bedford is 99.

Donny always makes me laugh as they fail you for being 101db then a jet lands overhead sending the meter to 160db plus.

[DocJock]

shim said:

i had been to bedford 3 times in stock M3CSL and no noise issues at all on static or driveby test.

It's very weather dependant shim. He has problems on damp/humid days. Pretty sure it's induction noise that screws him.

[shim]

ok that may be so but i have been on wet and dry days.

next back there on the 14th April so hopefully i dont fall foul fo those meters!

[Gms]

As DocJock said the limits are very rigid.
Unfortunately I was one of the three people who got black flagged
at that SIDC day many years ago.
Have been back many times since and never had problem.
Having said that the Scooby was bloody noisy and my current car is as quite
as a mouse in comparison.
Hope to see you there in the new car, only got it 5 days ago so should be able to
put a few miles on it before to run it in.

Edited by Gms on Friday 30th March 22:11

[jleroux]

batman69 said:

If you did Donny you'll be fine.

Wrong! The noise is measured differently at the two circuits so you can't do a direct comparison.

batman69 said:

I believe the drive by at bedford is 99.

Wrong! It's 87.5dB but from 20m as opposed to the 98dB at ~10m at Donny.

batman69 said:

a jet lands overhead sending the meter to 160db plus.

160dB is enough to shatter glass so I think that's a bit of an exaggeration. Believe it or not, the airport are actually subjected to the same average noise levels as the circuit - it's just that they fill up their "average noise level bucket" in short bursts rather than continuous drones. Stood at the track its actually very rare for one of the jets to exceed 108dB.

Jonny
BaT

[rs48635]

as with anything don't assume - check first. Bedford will noise test you for free before the event, useful only if you are local.
I failed the static in a standard 911 (1984 3.2 carrera) at 104Db :-(
Not the end of the world as you can still play if you pass the drive-by, which I did no problem. Good to get two laps with local instructor driving to learn the circuit. Bit embarrased to be in the sin bin with monster Skyline and Supra both heavily modified.

[shim]

i have the sticker still on my windscreen from a trackday test in October (green star) and they just waved me past the last two visits without testing.

Will try again next week!