Track day noise

[PVCGriff]

I have a rather noisy pre-cat & would like to take car on track day at Goodwood. Noise limits are 98db on certain days, 105db on others. Could somebody give me an idea of likely ability of car to pass these limits with or without additional silencers (if needed - any recommendations?). Are there places that one can have noise levels checked?
Any advice much appreciated.
Cheers, Nigel

[LordGrover]

If your exhaust system is standard you should get in below the 105db limit but may struggle for the 98. Usually. If you pop along to the Growl there's usually a noise competition so a db meter is on hand. Probably.

[davep]

I'd err on the side of caution and assume that a pre-cat will fail if not the static then the dynamic noise checks at Goodwood. Inserts are usually available from ACT, alternatively you could place a wanted ad.

[rico23]

You should be able to go along to your local circuit when there is a track day on and ask to have your car noise tested for free. There usually friendly and it's a great opportunity to test the different noise levels at different rpm so you know exactly how close or beyond the limit you are.

Bear in mind though that if you pass a static there are also drive by tests to contend with. At Bedford so ive been told they have microphones track side that go straight to the council offices!

[griffter]

My 4.3 was around 100 depending on the atmospherics on the day. Inserts are neat but bolt on silencers are more effective. Mine dropped under 90 db with bolt ons.

[griffdude]

In my experience 98db is unobtainable on std pre cat exhaust & additional 'cans', but got 102db with cans so the noisier days are the one to go for.

Incidentally having a chat about Bedford last night & was told that if you breech the levels on the drive by meters once you are off......

[rico23]

griffdude said:

In my experience 98db is unobtainable on std pre cat exhaust & additional 'cans', but got 102db with cans so the noisier days are the one to go for.

Incidentally having a chat about Bedford last night & was told that if you breech the levels on the drive by meters once you are off......

It's harsh! Cadwell Park is probably the best in the country noise level wise. Much more relaxed as the circuit is in a valley not near very much.

[leerdam23]

Goodwood is very tough on noise. I'd get the noise level measured by the guys at goodwood before the track day, rather than assuming that a measurement somewhere else will be the same. My car is unchanged from venue to venue (for sprinting) and anywhere from 98 to 108 dB. If goodwood say it is ok then you have a far better chance of being ok on the track day.

[7 TVR]

A set of good silencers on the back and you'll get on any 105 day, as for 98 days never bothered!
I have a sound meter if you want to test your exhaust?? I'm in Richmond SW London

[PVCGriff]

Brilliant rapid response, chaps. Think I'll take advice of popping down to Goodwood sometime soon & getting levels checked - especially if measuring does vary in accuracy from venue to venue.
Thanks
Nigel

[davemac250]

Tvrmonster has inserts for sale via eBay shop.

Make a reported 8% drop in noise.

[JamesK]

Funnily enough I was at Goodwood today so can add my 2p

I have a 4.5BV which is at least as loud as any pre-cat I've ever heard. It was a 105db day and as others have said, goodwood are very stringent with noise due to needing residents onside for the revival etc. Having said that they are very fair from what I saw.

They did my static reading at 4.5k which I thought was high - measured 104 so I passed. A tubi'd 355 failed but they had a word and let him on later asking that he short shift to keep it reasonable - I felt that was really good of them.

Bottom line is I'm not convinced any pre-cat would get under 98 but 105 you should be fine. Later, catted cars seem much quieter if standard.

hth

Edited by JamesK on Monday 14th May 20:59

[red griff roger]

Make sure your engine is nice and warm before the test.

[haircutmike]

I'm in Surrey, you can always borrow a pair of clamp ons, I have a few!

[SILICONEKID340HP]

davemac250 said:

Tvrmonster has inserts for sale via eBay shop.

Make a reported 8% drop in noise.

Yes i have some , i also use them on the road for long journeys

[PVCGriff]

haircutmike said:

I'm in Surrey, you can always borrow a pair of clamp ons, I have a few!

Many thanks for the offer, very kind. I hope to get down to Goodwood tomorrow for a noise test. If the car struggles to meet the limit I may well come back to you.

Kind regards
Nigel

[PVCGriff]

Good news. Had car tested at Goodwood this morning. Well within limits for 105db day and 98db should be attainable with bolt-on silencers. Need to decide on a day now!
Thanks for help & suggestions everyone.
Regards
Nigel

[haircutmike]

PVCGriff said:

Good news. Had car tested at Goodwood this morning. Well within limits for 105db day and 98db should be attainable with bolt-on silencers. Need to decide on a day now!
Thanks for help & suggestions everyone.
Regards
Nigel

Why not do Castlecombe on 9/7/12 @ £135.00, several other tivs attending.

http://www.pistonheads.com/gassing/topic.asp?h=0&a...