Invidia N2 + Tomei UEL Headers Decibels

[YSoAggressive]

This is just a rough estimate. By no means is this a professional reading but it gives you an idea. Also keep in mind I used some cheap decibel reader off of Amazon that was like 20 bucks so not the most accurate I would assume. About 70 degrees Fahrenheit at the time of recording this as well if that means anything. Just did some minor sound testing with my Invidia N2 Catback + Tomei UEL headers and inside the cabin I got anywhere from 78db to 88db (cruising and accelerating speeds). Then I went to an open area where sound couldn’t echo very much, had a buddy stand about 10 feet from the left exhaust and revved to 4k reaching about 98 - 101db. Revved 3k and got about 92 - 95db readings. Didn’t test the right side unfortunately or middle between the two exhausts just left side 10 feet approximately away from it.

[Breezio]

The only way to compare db measurements is to use the exact same testing parameters.
Mostly consist of:
Distance from subject
Angle from subject
Height testing device is from ground
'Condition' of testing subject
There are also specific settings on the db meter that need to be used.

As an example SCCA's official test procedure for Solo events (autocross) is:
50' from course.
Perpendicular to course/car
Section of track where subject will be wide open throttle.

Tester settings, I don't remember precisely, but I believe it needs to be 3' off the ground.

[YSoAggressive]

Originally Posted by Breezio

The only way to compare db measurements is to use the exact same testing parameters.
Mostly consist of:
Distance from subject
Angle from subject
Height testing device is from ground
'Condition' of testing subject
There are also specific settings on the db meter that need to be used.

As an example SCCA's official test procedure for Solo events (autocross) is:
50' from course.
Perpendicular to course/car
Section of track where subject will be wide open throttle.

Tester settings, I don't remember precisely, but I believe it needs to be 3' off the ground.

You are absolutely correct and that’s why I said that my numbers aren’t any official values by any stretch of the imagination because I didn’t really follow a lot of these parameters. However, there seems to be no information regarding any sort of decibel readings on this catback, let alone combined with the headers and I know there are at least a few people out there wondering how it could perhaps stack up to other exhausts volume wise. This shows that this exhaust is indeed loud where the general consensus is that it was pretty quiet and it gives merit as to why it drones so damn much for the small majority who do have it. Unfortunately just not enough information surrounding this exhaust so nobody I can go to if I wanted comparisons to it.

[Breezio]

101 db at that distance on a free rev is indeed pretty loud unless you got some pops/bangs that could have skewed it.

[YSoAggressive]

Originally Posted by Breezio

101 db at that distance on a free rev is indeed pretty loud unless you got some pops/bangs that could have skewed it.

No pops and bangs because I still have stock front pipe and over pipe. Just Invidia N2 Catback with Tomei UEL headers which are Catless so one missing cat. Now I’m wondering what sort of DB readings I can expect of the Tanabe Concept G single exit with Catless UEL headers

[EndlessAzure]

You should try measuring them according to the California Code of Regulations, Exhaust System Measurement instructions: 13 CCR § 1036 (LINK)



Microphone level to the exhaust tip height (or 8 inches above ground if the tip is lower)

20 inches away from the exhaust tip @ 45 degree angle from straight (away from vehicle centerline)
Engine revs held steady at 75% max RPM

[YSoAggressive]

Originally Posted by EndlessAzure

You should try measuring them according to the California Code of Regulations, Exhaust System Measurement instructions: 13 CCR § 1036 (LINK)



Microphone level to the exhaust tip height (or 8 inches above ground if the tip is lower)

20 inches away from the exhaust tip @ 45 degree angle from straight (away from vehicle centerline)
Engine revs held steady at 75% max RPM

I’d imagine from that length the revs would be around 105 - 108db because it’s so much closer. 75% would be like how much rpm? sorry I’m sped

[EndlessAzure]

Originally Posted by YSoAggressive

I’d imagine from that length the revs would be around 105 - 108db because it’s so much closer. 75% would be like how much rpm? sorry I’m sped

Redline is 7400 RPM. 75% of that is about 5500