Southern GT40 - Track Day Decibel Rating

[Jay Gadsby]

A question for anyone with a Southern GT40 with the "standard" out of the factory "silencers".

I'm planning some track sessions for this year and want to try and find out if anyone has had their SGT40 tested and if so what was the decibel reading.

My engine/motor is a 347 and I have -

1) a nice set of straight through pipes!
2) the silencer boxes as supplied by SGT which would be well packed.

Anyone know what these two setups might produce sound level wise.

Thanks
Gratuitous photo included for extra interest

 

[Nick]

Hi Jay,

Afraid it doesn't really answer your question but may provide an idea. I suspect your factory silencers will be like mine, which if so mean they can be packed with more wadding or wadding removed depending on how loud you want them.

Nick

PS gratuitous photos always appreciated by me

 

[Jay Gadsby]

Hi Jay,

Afraid it doesn't really answer your question but may provide an idea. I suspect your factory silencers will be like mine, which if so mean they can be packed with more wadding or wadding removed depending on how loud you want them.

Nick

PS gratuitous photos always appreciated by me

Nick, gratuitous photo of yours would beat mine

 

[Glenn M]

Nick, gratuitous photo of yours would beat mine

Southern GT sell a pair of boxes which will get you down to around 100db without any wadding.

 

[Jay Gadsby]

Southern GT sell a pair of boxes which will get you down to around 100db without any wadding.

Thanks Glenn,
They will be the oval ones?
Are they the ones you used during your time?
Did you have any other setup that worked within limits?

 

[Glenn M]

Yes, the same.
I started out with wadding and inserts etc. but it was all so hit and miss, never knowing if it was going to make the limit.
Their oval silencers gave such peace of mind, knowing I would get in. In fact, I turned up to a 98db day once by mistake and still got through... although struggled with the drive by meters I admit.

 

[Jean-Marc]

To reach 100db is relatively easy with off the shelf exhaust devices. But the goal is to reach 95db the standard limit for european race tracks.

 

[Jay Gadsby]

To reach 100db is relatively easy with off the shelf exhaust devices. But the goal is to reach 95db the standard limit for european race tracks.

Thanks for your input, Jean.
It's Spa I'm scheduled for again and the limit is 103 dB on that day.
I'll be looking at add on devices, for sure.

It looks like it's 107 dB static
103 dB dynamic - so that's a bit better to plan for.

 

[Jay Gadsby]

Yes, the same.
I started out with wadding and inserts etc. but it was all so hit and miss, never knowing if it was going to make the limit.
Their oval silencers gave such peace of mind, knowing I would get in. In fact, I turned up to a 98db day once by mistake and still got through... although struggled with the drive by meters I admit.

Thanks again, it's helpful to get a bit of a picture of past experiences.

 

[Jean-Marc]

Jay, Spa is almost an exception in Europe, imagine, Dijon a formal Formula 1 track is asking now 95db. dynamic on the strait line. When you know where the micophone is placed, you remove the foot from the accelarator just before to reach it.