R500 Noise for Track Days

[steve z]

I'm posting this on behalf of a friend who has just bought a series 1 R500 and he wants to track it with Goldtrack at Silverstone.

The noise limit is 98dB for the day.

Without any baffling he thinks its c.105dB, so the question is whats the best way to get it down to 98dB?

[BertBert]

Looks like a tough one to get to 98db then. Needs an airbox and a quieter exhaust (and probably prayer).
BErt

[rubystone]

I can't see him getting below 102db with both airbox (with snorkels) and a decent silencer (eg 7.25 inch Raceco). I think he'll need to fit a rear-exit exhaust to get him down below 98db. There are plenty of noisy days thoguh - Brands Indy, Donington, Cadwell, Snetterton all have 105db days.

You don't say whether that 98db is drive-by or static. If it's the former, he won't stand a chance!

[BertBert]

mmmm, are we actually in agreement on something?

Rear exit plus reverie/caterham snorkel/gas mask airbox would do it.

Bert

[martin thomas]

Goldtrack silverstone gp days are usualy 110db. 105db for evenings.They usualy have some very noisy machines there with no probs.


Martin

[steve z]

martin thomas said:

Goldtrack silverstone gp days are usualy 110db. 105db for evenings.They usualy have some very noisy machines there with no probs.


Martin

The one in mid-August is 105dB during the day and 98dB in the evening.

[Bobo W]

In addition to the forementioned you could also consider a merlin muffler which does a great job on my car and means you can do great impressions of Bodicea

[rubystone]

BertBert said:

mmmm, are we actually in agreement on something?

Rear exit plus reverie/caterham snorkel/gas mask airbox would do it.

Bert

[edb49]

Just dragging this one up as I managed to do all of one lap of Bedford before being thrown out due to noise on my Duratec R500.

I've got the track day exhaust & airbox, so the car is as quiet as it can be from the factory. Also got the sequential box, but I am not sure how much that contributes to noise if at all.

Static - 96.3db @ 4300rpm (limit was 101db)
Drive by - 90.1db @ 8500rpm (limit was 87.5db, I think they measure at 20 metres)

Any tips on what I can do to get the car within noise restrictions?

[rubystone]

They are being picky. Those are good figures IMHO. I'd say stick two fingers up to Bedford, after all, why waste time on a place like that when you can drive a real race circuit that MSV own such as Cadwell, Brands or Snetterton...all of which have plenty of "noisy" (105db) days.

[edb49]

rubystone said:

They are being picky. Those are good figures IMHO. I'd say stick two fingers up to Bedford, after all, why waste time on a place like that when you can drive a real race circuit that MSV own such as Cadwell, Brands or Snetterton...all of which have plenty of "noisy" (105db) days.

Yep, Cadwell/Snet are too far away for me really, I'm in Berkshire so Bedford is a good location for me. I'd be happy to sacrifice a few BHP to have no trouble at circuits with noise. I've worked out the 90.1db @ 20 metres is 122db @ 0.5 metres, does that sound possible a Caterham was making that much noise?