Test Pipes Decibel Level.
 

Hi guys,

Does anyone have a Stillen/Fast Intentions exhaust and test pipe combo? Additionally if you have headers this would be helpful to.

I am looking at installing test pipes to my existing exhaust system, however where I live exhaust systems for a V6 vehicle must be under 90 Decibels at 3200rpm.

Would someone be able to measure their test pipe and exhaust system setup to 3200rpm on a decibel meter and post the results and list their modifications? If not possible to get it exact just to 3000-3500rpm.

I would greatly appreciate this as with conversion rate and import taxes these test pipes will cost me close to $600 and if I have to sell them it will be near impossible as the 370z is quite rare in NZ. Not to mention the disappointment of not being able to have them on the car.

Thanks a lot,

Visser51.



Sent from my SM-G935F using Tapatalk

Here is the only thing I could find on this, which isn't really helpful: SCCA Exhaust db Limit

I have a non resonated, carbon fiber Fast Intentions CBE with Berk HFCs. I would be happy to do a test for you, but I don't have a meter.

Rusty is running FI headers and an FI CBE. I wonder if he has a meter?

Also, there is going to be a big sound difference with the FI CBE depending on which system you decide to go for: 12" resonators, 18" resonators or non resonated.

Also, do you know at what distance the dB level is being measured? That has a big impact.

Hi JLarson

Good point.

I have directly copied and pasted what the requirements of our noise test requirements are below for you.

Test site requirements


2.2(1) A test site used in the application of this standard must be an open outdoor site that:


(a) is predominantly flat, particularly within the immediate test area; and


(b) incorporates within a radius of not less than 3 metres (10 feet) from the

sound level meter microphone:


(i) a space free from large sound-reflecting surfaces including

buildings, walls, billboards, vehicles, trees, or shrubs; and


(ii) a solid surface such as concrete or asphalt, free of any loose or

sound-absorbing material.


2.2(2) Exhaust noise emission testing on a low volume vehicle may be carried out under

a canopy, provided that no part of the canopy, including its supports, are within 3 metres (10 feet) of the sound level meter microphone.


NOTE: Accurate and repeatable exhaust noise emission test results can only be obtained by using a location

with a solid ground surface and no major sound reflecting surfaces, such as a large car park.

Regards,

Visser51

Sent from my SM-G935F using Tapatalk

Hi Spartan 1771, thanks for responding.

Honestly I'm not all too sure about the resonated part of the exhaust. From my knowledge it seems the longer the exhaust is resonated e.g 18" opposed to 12", the quieter the exhaust becomes in the cabin e.g less drone.

Is this the case? Will it also make it quieter outside the car? If so I will probably go with the most possible resonation.

Thanks for bearing with me, I am new to 370z modifications and this is my first post on this site.

Regards,

Visser51.

Sent from my SM-G935F using Tapatalk

I would suggest you look on Fast Intentions website: https://www.fastintentions.com

You have several options when ordering your exhaust from them. One of which is resonator options. You have three to choose from:
1. Non-resonated - Loudest option
2. 12" resonators - in the middle
3. 18" resonators - quietest option

I would say your best bet would be to go with the 18" resonators. You also have the option of adding race cats. I believe these will cut down on rasp, keep you somewhat green and keep your back bumper from getting black residue on it.

Hey again

Yeah I'll email them the same equiry

Sent from my SM-G935F using Tapatalk