Just doing some curious measurements, and readings to see how loud exhaust is on G models. Measurements done at warmed up temperatures.

For those who have a First Generation G35, first or second series sedan:Idle Db reading: 53 dbFull throttle: 87 db

If you have a coupe/fx midpipe like me:Idle: 58 dbFull Throttle: 92 db

G35 coupe series 1:Idle: 61Full Throttle: 94

G35 coupe series 2:Idle: 59Full Throttle: 92

For G37 coupes:Idle: 57dbFull Throttle: 96dbIf you remove the rear muffler, see the video I'll post this evening, and know you'll be Illegal in 40 states, since you'll be doing:Idle: 56 dbFull throttle: 109 db

FX50Idle:56dbFull Throttle: 92.5 db

I'll post up other cars as well soon
Modified by Poyzinous at 4:25 PM 6/11/2009

good info

I wish someone else would show appreciation for my time and research...

Yeah I cant post the vid. Its too screwed up. Should have focused more on recording it.

Nice....are the sedan levels the same?....my car seems two times louder than the 09 g37 loaner that I had last month. And I have a stock exhaust.

Don't fret Gabe, we all appreciate your efforts in thwarting the evil work monster.

In all honest I did not expect some of those results. We need to add some science to this, in the form of some standards for this test. If we get some free time I say we make a stand for your decibel meter and set a standard distance and load percentage to establish a base line we can use to compare aftermarket exhaust systems against the OE.

I am pretty surprised that the old coupes are that loud.

I am a willing guinnee pig for the after market exh. The next time I am in the NOVA are, I will let you know. You can get a dB test of my Fast Intentions exh. I am also interested in seeing the dB levels of different intakes as well.

I know my Nismo intake is MUCH louder then my exh until around 5K.

I would have thought the 1st gen exh to have been loader. I used to get all kinds of comments on how good it sounded at stop lights. From people who were following me and then when they were beside me. I always got asked it was stock. Everyone loved the sound of it.

SteveTheTech wrote:Don't fret Gabe, we all appreciate your efforts in thwarting the evil work monster.

In all honest I did not expect some of those results. We need to add some science to this, in the form of some standards for this test. If we get some free time I say we make a stand for your decibel meter and set a standard distance and load percentage to establish a base line we can use to compare aftermarket exhaust systems against the OE.

I am pretty surprised that the old coupes are that loud.

I'm not surprised at all. The newer models of both the coupe and sedan are much quieter than their respected predessors , which I find sad. It makes me love my 03 3even more and less interested in upgrading to a 09.

SteveTheTech wrote:
I am pretty surprised that the old coupes are that loud.

Steve, and Mrsmith guy,The G37 is louder by 2db than the first series G. The 2nd series Gcoupe (and Fx, actually) got different rear mufflers that made the car quieter. And although some systems may sound louder, remember that there are different frequencies and whatnot, decibels are a measure of sound intensity. A Vacuum can be as loud as a jet plane, but not many people could distinguish that, because of perception and different sound types. Also, From inside they sound different because of resonance tuning and soundproofing. the V36 models have a dual setup, and sound vibrations dont mix up like in the V35 models where both banks release from the same muffler. That also helps in varying and spreading the sound so it isn't as loud from a direct point. Tomorrow I'll test a V36 sedan so be ready Steve. I also want to test an M.

Poyzinous wrote:I wish someone else would show appreciation for my time and research...

Dude...your efforts and contributions NEVER go un-noticed and your contributions to NICO are VERY much appreciated

I'm guilty lately of reading and editing threads but not responding as much. I just got alot on my plate right now.

Trust me, you are a great asset to NICO so for that I Thank you!



I am surprised that the 1st gen coupes are 2db louder then 2nd gen??

you've got it backwards sean. The first gen is 2 db quieter than the 2nd gen. The first generation G measures 94 for the first series 03-04 and 92 for the second series 05-06. They got a different muffler design. So did the FX. The second gen registers 96db since it uses a split dual exhaust system and maybe the .2 liter displacement boost.

There are some interesting numbers.

Looking forward to see the #'s on the V36.

Poyzinous wrote:
G35 coupe series 1:Idle: 61Full Throttle: 94

SO, my coupe is loud and proud!!

Great post!!

I know when I leave the track my ears ring just about until I get home (big V8's - no exhaust/mufflers)...

I'm sure the sedan's stock midpipe is the culprit for their low DB readings... however.

I think my car is sooo loud right now, when I tromp it under an overpass, I can actually (and have) scared people right off the road. I was coming behind a saturn or something last week, and I slammed it, dropped to third and WOT under that bridge... I couldn't believe the audible sex resonating acoustic reverbrations reaching my ears.

Either could the poor driver of the Saturn, they went way off on the shoulder right after spooked them I swear it's pretty loud at 4-6K WOT - especially with the blox spacer. Audiosex.

The VQ35 is a Big bore motor, so the intake is loud and I've noticed too sometimes when I stomp it, people in front of me hit their brakes cautiously. The Mid pipe is the reason the sedans are quiet. Its a muffler muffling exhaust into another muffler, as opposed to a resonator soothing the flow into a muffler. Plus the 30lbs of weight savings.

kmckis1029 wrote:good info

I still haven't gotten my Exhaust done yet.... I haven't forgotten about you!

DJ

Tampa G35 Sedan 6MT wrote:
I still haven't gotten my Exhaust done yet....

How come your sig says you have.... stuff. I cant see the sig when I'm writing a post. Gosh darnit. I want to hear your exhaust. I have a 70 Series lying around somewhere...

Steve and I will be doing a post here that MANY of you may want to consider. It will be very informative, and hopefully you'll learn something.We're going to begin working on it very soon. Maybe tomorrow if its slow.

You guys are awesome