Nissan 370Z Forum  

Tips for lowering dB? (Tomei expreme Ti)

Does anyone have tips on how to quiet this exhaust down? NCM has a 103dB limit at 50 feet and I doubt installing the silencer do much to help meet

Go Back   Nissan 370Z Forum > Nissan 370Z Tech Area > Track / Autocross / Drifting / Dragstrip


Like Tree30Likes

Reply
 
LinkBack Thread Tools Display Modes
Old 11-13-2017, 11:10 AM   #1 (permalink)
Base Member
 
Join Date: Dec 2015
Location: Smyrna, TN
Posts: 115
Drives: 12 Nissan 370Z MB M6
Rep Power: 9
Laomatik is on a distinguished road
Default Tips for lowering dB? (Tomei expreme Ti)

Does anyone have tips on how to quiet this exhaust down? NCM has a 103dB limit at 50 feet and I doubt installing the silencer do much to help meet this level especially since the installation of test pipes.

Are there any products (baffles, turn downs) that can be easily adapted to the exhaust? Or will a custom solution be needed so I can run at NCM?

Thanks in advance for any advice.
Laomatik is offline   Reply With Quote
Old 11-13-2017, 11:34 AM   #2 (permalink)
Base Member
 
echoshotz's Avatar
 
Join Date: May 2015
Location: Knoxville, TN
Posts: 218
Drives: 14 Nismo
Rep Power: 72
echoshotz has a reputation beyond reputeechoshotz has a reputation beyond reputeechoshotz has a reputation beyond reputeechoshotz has a reputation beyond reputeechoshotz has a reputation beyond reputeechoshotz has a reputation beyond reputeechoshotz has a reputation beyond reputeechoshotz has a reputation beyond reputeechoshotz has a reputation beyond reputeechoshotz has a reputation beyond reputeechoshotz has a reputation beyond repute
Default

probably going to need to do something custom. This is the reason I got rid of my Tomei. they did however just come out with a v2 silencer you can find on Z1's site that *may* work. But the tomei is just so loud I doubt it
Brendan likes this.
__________________
2014 Solid Red Nismo 370z
Motordyne|Synergy Composites|Stance Suspension|Recaro|RJM|EVOR
echoshotz is offline   Reply With Quote
Old 11-13-2017, 01:44 PM   #3 (permalink)
Base Member
 
Join Date: Dec 2015
Location: Smyrna, TN
Posts: 115
Drives: 12 Nissan 370Z MB M6
Rep Power: 9
Laomatik is on a distinguished road
Default

Quote:
Originally Posted by echoshotz View Post
probably going to need to do something custom. This is the reason I got rid of my Tomei. they did however just come out with a v2 silencer you can find on Z1's site that *may* work. But the tomei is just so loud I doubt it
Thanks for the heads up, I wasn't aware of the v2 silencer. Maybe if I have a turn down added to it as well as some baffles on the inside I can reach my dB goal... I refuse to give up my Tomei lol.
Laomatik is offline   Reply With Quote
Old 11-13-2017, 01:49 PM   #4 (permalink)
A True Z Fanatic
 
Join Date: Dec 2009
Location: 03350 Australia
Posts: 1,502
Drives: 09 Nissan 370Z M6
Rep Power: 29907
BGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond repute
Default

There is a product called a spiral silencer which I use on my race car. I don't have a US reference but you might want to check Spintech Mufflers who are US based. Google should help out
BGTV8 is offline   Reply With Quote
Old 11-13-2017, 10:19 PM   #5 (permalink)
Ronin Samurai - Assassin
 
Rusty's Avatar
 
Join Date: Dec 2011
Location: Fayettenam,Pennsyltucky
Age: 68
Posts: 34,811
Drives: 2011 Nismo GM 6M
Rep Power: 2684436
Rusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond repute
Talking

If you know what side of car the meter will be on. You can add turn downs that point away from that side. I've seen guys do that.
gomer_110, danegrey and Elmo370z like this.
__________________

浪人 - 殺し屋
"The Difficult Anytime, The Impossible By Appointment Only"
http://www.the370z.com/members-370z-...o-journal.html
Rusty is offline   Reply With Quote
Old 11-14-2017, 05:58 PM   #6 (permalink)
Track Member
 
Join Date: Apr 2013
Location: Colorado
Posts: 623
Drives: Poor man's Porsche
Rep Power: 541
Brendan has a reputation beyond reputeBrendan has a reputation beyond reputeBrendan has a reputation beyond reputeBrendan has a reputation beyond reputeBrendan has a reputation beyond reputeBrendan has a reputation beyond reputeBrendan has a reputation beyond reputeBrendan has a reputation beyond reputeBrendan has a reputation beyond reputeBrendan has a reputation beyond reputeBrendan has a reputation beyond repute
Default

found a promo video for the tomei silencer

https://www.youtube.com/watch?v=emHA...ature=youtu.be

the last one sounds about as loud as a cat fart. may be your best option.
Zbrah likes this.
Brendan is offline   Reply With Quote
Old 11-14-2017, 06:21 PM   #7 (permalink)
Ronin Samurai - Assassin
 
Rusty's Avatar
 
Join Date: Dec 2011
Location: Fayettenam,Pennsyltucky
Age: 68
Posts: 34,811
Drives: 2011 Nismo GM 6M
Rep Power: 2684436
Rusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond repute
Talking

Quote:
Originally Posted by Brendan View Post
found a promo video for the tomei silencer

https://www.youtube.com/watch?v=emHA...ature=youtu.be

the last one sounds about as loud as a cat fart. may be your best option.
This comes to mind.
Attached Images
File Type: jpg car-with-cat-in-muffler.jpg (61.4 KB, 56 views)
__________________

浪人 - 殺し屋
"The Difficult Anytime, The Impossible By Appointment Only"
http://www.the370z.com/members-370z-...o-journal.html
Rusty is offline   Reply With Quote
Old 11-14-2017, 07:06 PM   #8 (permalink)
A True Z Fanatic
 
gomer_110's Avatar
 
Join Date: Aug 2011
Location: Perrysburg, OH
Posts: 17,992
Drives: '11 Nismo #528 GM
Rep Power: 36940
gomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond repute
Default

While I can't give you a link to one, I've seen inserts that go in the end of the muffler that are designed to reduce the sound.

Also the turndown idea works pretty well. Even just pointing the turn down at the ground can make a big difference. Not sure the diameter of the tomei muffler tip but I've commonly seen autoxers use a HVAC duct elbow as a turn down with just a hose clamp holding it on.
__________________
'11 370Z Nismo #528 Fast Intentions | Stillen | Motordyne | Uprev | CSF | Zspeed | Z1 Motorsports | AST | Swift | SPC | SPL | Whiteline | Hotchkis | Bride | Schroth | Robispec | Cusco | Nismo | Volk | Forgestar | Hoosier | RJM
'17 Titan Bone Stock
gomer_110 is offline   Reply With Quote
Old 11-15-2017, 07:19 AM   #9 (permalink)
Base Member
 
Join Date: Dec 2015
Location: Smyrna, TN
Posts: 115
Drives: 12 Nissan 370Z MB M6
Rep Power: 9
Laomatik is on a distinguished road
Default

Quote:
Originally Posted by BGTV8 View Post
There is a product called a spiral silencer which I use on my race car. I don't have a US reference but you might want to check Spintech Mufflers who are US based. Google should help out
Is that for a full muffler? I was hoping for something to add to my silencer and be able to take on and off.
Laomatik is offline   Reply With Quote
Old 11-15-2017, 07:21 AM   #10 (permalink)
Base Member
 
Join Date: Dec 2015
Location: Smyrna, TN
Posts: 115
Drives: 12 Nissan 370Z MB M6
Rep Power: 9
Laomatik is on a distinguished road
Default

Quote:
Originally Posted by Rusty View Post
If you know what side of car the meter will be on. You can add turn downs that point away from that side. I've seen guys do that.
Left side coming out of turn 2b onto a straight... I've thought about a turndown to the ground but maybe pointing it away from them will work better?
Laomatik is offline   Reply With Quote
Old 11-15-2017, 07:23 AM   #11 (permalink)
Base Member
 
Join Date: Dec 2015
Location: Smyrna, TN
Posts: 115
Drives: 12 Nissan 370Z MB M6
Rep Power: 9
Laomatik is on a distinguished road
Default

Quote:
Originally Posted by gomer_110 View Post
While I can't give you a link to one, I've seen inserts that go in the end of the muffler that are designed to reduce the sound.

Also the turndown idea works pretty well. Even just pointing the turn down at the ground can make a big difference. Not sure the diameter of the tomei muffler tip but I've commonly seen autoxers use a HVAC duct elbow as a turn down with just a hose clamp holding it on.
Will the HVAC duct hold its shape at track speeds?
Laomatik is offline   Reply With Quote
Old 11-15-2017, 07:53 AM   #12 (permalink)
A True Z Fanatic
 
gomer_110's Avatar
 
Join Date: Aug 2011
Location: Perrysburg, OH
Posts: 17,992
Drives: '11 Nismo #528 GM
Rep Power: 36940
gomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond repute
Default

Quote:
Originally Posted by Laomatik View Post
Will the HVAC duct hold its shape at track speeds?
It's only an elbow piece I'm talking about so I would think so. I know they do just fine at speeds approaching 90 mph. No knowledge beyond that but I wouldn't see any reason they would deform.
__________________
'11 370Z Nismo #528 Fast Intentions | Stillen | Motordyne | Uprev | CSF | Zspeed | Z1 Motorsports | AST | Swift | SPC | SPL | Whiteline | Hotchkis | Bride | Schroth | Robispec | Cusco | Nismo | Volk | Forgestar | Hoosier | RJM
'17 Titan Bone Stock
gomer_110 is offline   Reply With Quote
Old 11-15-2017, 09:02 AM   #13 (permalink)
Base Member
 
Join Date: Dec 2015
Location: Smyrna, TN
Posts: 115
Drives: 12 Nissan 370Z MB M6
Rep Power: 9
Laomatik is on a distinguished road
Default

Quote:
Originally Posted by gomer_110 View Post
It's only an elbow piece I'm talking about so I would think so. I know they do just fine at speeds approaching 90 mph. No knowledge beyond that but I wouldn't see any reason they would deform.
Something like this?

https://www.amazon.com/Duct-Elbow-De.../dp/B00BLUA5Z8

I think that could actually work. I just hope it's enough. Does anyone know of any cheap decibel meters I can use to test?
Laomatik is offline   Reply With Quote
Old 11-15-2017, 09:05 AM   #14 (permalink)
A True Z Fanatic
 
JARblue's Avatar
 
Join Date: Mar 2011
Location: Austin, TX
Age: 43
Posts: 36,449
Drives: 11 Z34, 98 E36 M3
Rep Power: 2684440
JARblue has a reputation beyond reputeJARblue has a reputation beyond reputeJARblue has a reputation beyond reputeJARblue has a reputation beyond reputeJARblue has a reputation beyond reputeJARblue has a reputation beyond reputeJARblue has a reputation beyond reputeJARblue has a reputation beyond reputeJARblue has a reputation beyond reputeJARblue has a reputation beyond reputeJARblue has a reputation beyond repute
Default

Quote:
Originally Posted by Laomatik View Post
Does anyone know of any cheap decibel meters I can use to test?
Free iphone app? Or search Amazon.
__________________

2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed |
JARblue is offline   Reply With Quote
Old 11-15-2017, 09:22 AM   #15 (permalink)
A True Z Fanatic
 
gomer_110's Avatar
 
Join Date: Aug 2011
Location: Perrysburg, OH
Posts: 17,992
Drives: '11 Nismo #528 GM
Rep Power: 36940
gomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond reputegomer_110 has a reputation beyond repute
Default

Quote:
Originally Posted by Laomatik View Post
Something like this?

https://www.amazon.com/Duct-Elbow-De.../dp/B00BLUA5Z8

I think that could actually work. I just hope it's enough. Does anyone know of any cheap decibel meters I can use to test?
Bingo.

Here's a link to a picture of a 350z using one
Mariokart likes this.
__________________
'11 370Z Nismo #528 Fast Intentions | Stillen | Motordyne | Uprev | CSF | Zspeed | Z1 Motorsports | AST | Swift | SPC | SPL | Whiteline | Hotchkis | Bride | Schroth | Robispec | Cusco | Nismo | Volk | Forgestar | Hoosier | RJM
'17 Titan Bone Stock
gomer_110 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
[WTB] Tomei expreme ti exhaust Not_Z_but_G Parts for sale (Private Classifieds) 0 07-14-2017 12:26 AM
[WTB] Tomei expreme ti exhaust Silver09 Parts for sale (Private Classifieds) 1 11-12-2016 05:44 PM
[FOR SALE] Tomei Expreme Ti abm89 Parts for sale (Private Classifieds) 10 11-10-2015 10:48 AM
[FOR SALE] Tomei expreme ti Brady- Parts for sale (Private Classifieds) 6 09-22-2014 01:32 PM


All times are GMT -5. The time now is 04:18 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2