Decat Silencers

[Bear]

Anyone who uses one know how much a decat silencer reduced the noise of their car by on a flyby test ?? Reason I ask is that I was black flagged and kicked off Bedford Autodrome for measuring 90dB on the flyby test with a Mongoose !! I thought the Mongoose would be ok as it has two silencers on it but obviously it wasnt.

The flyby limit was 87.5db so I'm looking for something that will reduce the noise by at least 4dB on a flyby to be on the safe side.

 

[MrSix]

learn where they measure from and let off

 

[BigglesPiP]

You have a lot of work to do, you need to more than half the noise output.

 

[Berger]

Could you put the CAT back on the car I assume you run without one? Should dampen it down a little more?

 

[Bear]

learn where they measure from and let off

Where is the fun in that ?

 

[Bear]

Could you put the CAT back on the car I assume you run without one? Should dampen it down a little more?

That is an option but I want to see if I can make it more quieter without reducing the power if possible.

 

[Bear]

You have a lot of work to do, you need to more than half the noise output.

I know, the annoying thing was I was well inside the static 4.5k rpm 101dB limit where I was 83dB but I guess at full bore its considerably louder.

Shame really as it was a nice dry day and I was getting my bearings on the track and was flying.

 

[Marf]

That is an option but I want to see if I can make it more quieter without reducing the power if possible.

Unfortunately thats pretty unlikely.

Can you not get a bung?

 

[ineed2upgrade]

Get a faster car that's quieter?
Mongoose exhausts aren't known to be the quietest so you could try a different exhaust.unless your car is a turbo or highly tuned n/a putting the cat back on won't drop the power that noticably

 

[Berger]

Get a faster car that's quieter?
Mongoose exhausts aren't known to be the quietest so you could try a different exhaust.unless your car is a turbo or highly tuned n/a putting the cat back on won't drop the power that noticably

Its a highly tuned Nissan 200sx with about 400bhp iirc.

 

[djbenjo]

The mongoose is probably the quietest exhaust out there for the s14/a, apart from OEM obv. Imagine it with an Nur/Apex single

 

[Bear]

Get a faster car that's quieter?
Mongoose exhausts aren't known to be the quietest so you could try a different exhaust.unless your car is a turbo or highly tuned n/a putting the cat back on won't drop the power that noticably

Thats a bit of a jump isnt it ?? I'm talking about decat silencers and you are talking about buying another car !!!

 

[Bear]

Its a highly tuned Nissan 200sx with about 400bhp iirc.

I wish Its mildly tuned and running around 330bhp well 280bhp at the wheels

 

[thedazman67]

how about a sports cat should reduce the noise level without limiting performance much, i have the mongoose system on my s14a surely its not that loud is it.

daz

 

[Bear]

how about a sports cat should reduce the noise level without limiting performance much, i have the mongoose system on my s14a surely its not that loud is it.

daz

I guess it must be because thats what they measured before they kicked me off. I suppose it is possible that some of the baffle material could have been burnt off over time who knows

 

[AmDaMan]

My Janspeed one was as quiet as my cat.

 

[Gribs]

The apex decat silencers reportedly drop noise levels by about 10db though that's probably the static measure. However just sticking the cat back in makes a noticable difference and the power drop isn't that noticeable one you readjust the boost.