Nissan 370Z Forum - View Single Post - How loud is your aftermarket exhaust? A call for decibels

synolimit · 11-25-2013, 02:22 PM

I have a radio shack meter that only reads to 126db. I did 20" from the tip at tip level. I have a eBay LTH, top speed 2.5" OD X pipe with Helmholtz resonators installed at the X pipe to LTH connection, 2.5" ID 15.5" inline resonators in the 2.5" OD mid pipes and 2.5" OD straight pipes to 4" tips. My cars gutted so in cabin is louder. No complaints about the setup, no drone, mild rasp if you rev it when the rpms are coming down and mild hiss on decel also. Normal street driving it sounds stock quite! Above 5500rpm I challenge a better/exotic/raw/mean/amazing sound.

Cold start up, you know the first 20 seconds of really loudness, 116-121db
Cold warm up idle, 112-115db
Warm idle, 91-93db
In cabin highway windows up at 70mph, 93db
In cabin highway windows up at 80mph, 97-100db
In cabin windows down, 113db loudest I could get to redline
Outside free rev again at tips to 5k fuel/ignition cut, over 126db max
Loudest I could scream, 118db

Scary thing is before the Helmholtz I'd say everything was 10-20db higher!! Might do drive by's with the wife later.

11-25-2013, 02:22 PM	#41 (permalink)
synolimit A True Z Fanatic Join Date: May 2013 Location: Columbus, OH Posts: 5,051 Drives: 2013 Silver 370z Rep Power: 3389	I have a radio shack meter that only reads to 126db. I did 20" from the tip at tip level. I have a eBay LTH, top speed 2.5" OD X pipe with Helmholtz resonators installed at the X pipe to LTH connection, 2.5" ID 15.5" inline resonators in the 2.5" OD mid pipes and 2.5" OD straight pipes to 4" tips. My cars gutted so in cabin is louder. No complaints about the setup, no drone, mild rasp if you rev it when the rpms are coming down and mild hiss on decel also. Normal street driving it sounds stock quite! Above 5500rpm I challenge a better/exotic/raw/mean/amazing sound. Cold start up, you know the first 20 seconds of really loudness, 116-121db Cold warm up idle, 112-115db Warm idle, 91-93db In cabin highway windows up at 70mph, 93db In cabin highway windows up at 80mph, 97-100db In cabin windows down, 113db loudest I could get to redline Outside free rev again at tips to 5k fuel/ignition cut, over 126db max Loudest I could scream, 118db Scary thing is before the Helmholtz I'd say everything was 10-20db higher!! Might do drive by's with the wife later. __________________ 13 370z- Last edited by synolimit; 11-25-2013 at 02:33 PM.