Track day silencers

[hamish400]

I am planning to take the 400SE to Zolder this year, however the track has a 95dB noise limit.

Car was measured at 105-106dB at Nurburgring last year.

Has anyone any experience of add on silencers - such as the "supertrap muffler" as shown in Steve Heath's wedge bible (page 62). ie something that can be fitted while at the track, and taken off afterwards.

I have google searched for supertrap muffler but no supplier came up.

Any info on add-on silencers and suppliers would be welcome.

Rgds
Hamish

[rev-erend]

Hamish - time to start praying to your god

Seriously - 350Matt did a lot of track days and his wedge was the quietest one we measured on the day .. so he will know.

[dickymint]

Try ringing Tim Lamont here www.actproducts.co.uk/trackdays.php he will sort you out

[GreenV8S]

Supertraps tend to be relatively restrictive but can be very effective, you can get inserts that do a similar job, also external cans that can be very effective and minimal extra back pressure. Sean Hayes even used to have a complete full size expansion box slung sideways under the back of the car that reduced a rorty wedge to an inconspicuous murmur.

[number 7]

hamish400 said:

I am planning to take the 400SE to Zolder this year, however the track has a 95dB noise limit.

Car was measured at 105-106dB at Nurburgring last year.

Has anyone any experience of add on silencers - such as the "supertrap muffler" as shown in Steve Heath's wedge bible (page 62). ie something that can be fitted while at the track, and taken off afterwards.

I have google searched for supertrap muffler but no supplier came up.

Any info on add-on silencers and suppliers would be welcome.

Rgds
Hamish

Hamish, I 've been going to Zolder for a few years now, and although I always take a silencer which I bought from Tower View (inserts into the tailpipe and is secured with a small bolt - means drilling a small hole in the tailpipe) I've only used it once. It's true that the BBW's are noisy, and I was black-flagged for noise twice last year and IIRC three times the year before, you can get away without one at all, provided you lift off close to the meters around the circuit.

Look forward to seeing you there.

7.

[adam quantrill]

number 7 said:

provided you lift off close to the meters around the circuit.

In my car that would be the worst thing to do - nice loud pops and bangs when I lift off!

There muust be a better way - has anyone looked into active noise cancellation?

[ferlin]

Any chance of a picture of that insert no7 as I have been thinking of making myself one sometime.

[number 7]

ferlin said:

Any chance of a picture of that insert no7 as I have been thinking of making myself one sometime.

OK will get the camera out.

7.

[simonb9]

Does Zolder do track open days ?? As in you can just turn up on the day it is open and pay for a few laps or is it a dedicated track days where you have to pay up front for the whole day ??

[number 7]

simonb9 said:

Does Zolder do track open days ?? As in you can just turn up on the day it is open and pay for a few laps or is it a dedicated track days where you have to pay up front for the whole day ??

I think they do open test days, but the event I'm referring to is a TVRCC Holland one - I'm in the process of writting an article about it for the Wedgister which will explain all.

7.

[number 7]

Here we are - the pointy end goes into the tailpipe first and the whole thing is sits flush inside the pipe, secured by a bolt into a captive nut on the insert:




7.

[rev-erend]

I have often thought you could just buy a bag of wire wool - put it in the end of the exhaust and the put some gauze with a bit jubillee clip to hold it all in.. myself and many others have a sound meter if anyone every wants to try it and see how much difference it makes.

[ferlin]

Does the inner smaller diameter pipe go straight through? and the difference between the inner and outer plated in? if you know what i mean

[GreenV8S]

rev-erend said:

I have often thought you could just buy a bag of wire wool - put it in the end of the exhaust and the put some gauze with a bit jubillee clip to hold it all in.. myself and many others have a sound meter if anyone every wants to try it and see how much difference it makes.

Merlin Motorsport at Castle Combe will even sell you a bag of bits just for this. And it's a total waste of time, no silencing at all until you shove so much wadding in that it stifles the engine, and then it all blows out again. You need far greater volume for that sort of silencing to be effective.

[number 7]

ferlin said:

Does the inner smaller diameter pipe go straight through? and the difference between the inner and outer plated in? if you know what i mean

The inner pipe is almost straight through - the triangular cut-outs you can see are actually bent at 90 deg. into the gas flow for about half the overall length of the insert, and the gap between inner and outer tubes is filled to about half its length with steel wool.

7.

[hamish400]

Number 7,

Many thanks for all the info and for the pictures.

1. Do you have any measurements as to how many dB quieter your exhaust is when the insert is fitted?

2. From what you say, I assume Zolder uses "drive by" dB measurements rather than "static" dB measurements. Do you have any info as to how they relate for your car. The only measurements I have for my car are static readings.

Rgds
Hamish