Truenotch

Muffler Tech

Recommended Posts

Removing cat converter from 3AU 1500cc 4 banger, good practice to replace with resonator or not required? Will end up replacing most of the exhaust with 38mm tube and a new muffler as it's rusted out. So before I tuck the exhaust up too high, thought I better check about needing a resonator in there to keep things sounding as pleasant as it can. Don't want rasp.

Share this post


Link to post
Share on other sites

Will be louder.  So yeah  put something in its place if it only has one other muffler in the system

  • Thanks 1

Share this post


Link to post
Share on other sites

larger size piping with resonator and  turbo or baffle type muffler vs larger size piping with two turbo or baffle type mufflers vs  smaller piping with resonator and straight through muffler

thoughts on performance/loudness? e.g . say 2.5" vs 3" on 200hp engine

Share this post


Link to post
Share on other sites

reso and baffle type mufflers will cut out different noises,  so always good idea to have one of each, to try avoid having  drone or rasp. 

depends how the 200hp is being made.  something na with big cams and overlap  is going to work best with least exhaust pressure possible.   otherwise 2.5" will be plenty. 2.5" bit easier to make quieter,  although 3" doesn't have to be loud if done right.   

if going with a baffled muffler , i'd step up the muffler a size or 2.  as pretty much none of them will flow as much as the pipe size they are made for. no point running  big tube then putting a cork in the end of it

to try shut the starlet up with 3" system, i run 2 reso style straight throughs,, then an oversized baffled muffler at rear to keep flow up.  

  • Like 1
  • Haha 1

Share this post


Link to post
Share on other sites

Are there certain reso's that are better than others? Have seen a few brands (Coby, M&H), some with fibreglass, some with stainless fill. Worth upsizing muffler on a shit motor? 

Share this post


Link to post
Share on other sites

On range rover (4.6 V8) I put reso about 500mm after collector (2.5) then m&h flow master copy, 2.5 to the back. 

I just guessed where things would fit really, though I could move them around if need be. 

Roudy down low then gets quieter as revs increase. 

Anything to do with muffler placement? 

Shitty 60s tech RV8? 

Share this post


Link to post
Share on other sites
2 hours ago, Bling said:

Are there certain reso's that are better than others? Have seen a few brands (Coby, M&H), some with fibreglass, some with stainless fill. Worth upsizing muffler on a shit motor? 

Have driven a few cars with 3.5" exhausts, with adrenalin r straight through mufflers that work much better than you'd think - not that loud, no drone. All turbo cars though. 

Share this post


Link to post
Share on other sites
14 hours ago, kpr said:

reso and baffle type mufflers will cut out different noises,  so always good idea to have one of each, to try avoid having  drone or rasp. 

depends how the 200hp is being made.  something na with big cams and overlap  is going to work best with least exhaust pressure possible.   otherwise 2.5" will be plenty. 2.5" bit easier to make quieter,  although 3" doesn't have to be loud if done right.   

if going with a baffled muffler , i'd step up the muffler a size or 2.  as pretty much none of them will flow as much as the pipe size they are made for. no point running  big tube then putting a cork in the end of it

to try shut the starlet up with 3" system, i run 2 reso style straight throughs,, then an oversized baffled muffler at rear to keep flow up.  

this is on the 124 with supercharged 2L.  its 2.5" with a 2.5" coby and currently a 2.25" turbo style on the back as it was too noisy with a 2.5" straight through. both were just cheapies form chase. the whole thing is a bit crap as I have modified it a few times over the years and it gets banged up pretty often as there isn't much room to tuck things up under the 124 chassis which then makes vband clamps and flanges leak.

Also depending on how link/sequential tuning goes I could end up taking the S/C off and going turbo so Im thinking of going larger pipe size to future proof. Thinking oval tube so still 2.5" deep but 4" wide,  similar flow to between 3" and 3.5" . There really is only room for 2 silencing things,  one before the diff ~ 400mm x 225mm  and at the back similar size and has to be pretty shallow for a muffler, cant be much more than 125mm deep so no barrel type with dumpy tip may apply

11 hours ago, cletus said:

Have driven a few cars with 3.5" exhausts, with adrenalin r straight through mufflers that work much better than you'd think - not that loud, no drone. All turbo cars though. 

 good to know, I have been looking at their stuff, not cheap but when you compare to shipping similar spec stuff in it works out OK.

Share this post


Link to post
Share on other sites

if you want to make it better with what you have.  swap that 2.25 out with same design, but a 3".  keep pipe after muffler 2.5"  and shouldn't be much if any louder

But yeh if you are going to build a whole new system, with turbo a possibility.  what you have in mind should be good.  probably want to run a baffled muffler at rear supercharged  to keep noise down.  swap it out for a straight though if go turbo.  turbo stuff is easy to shut up

actually, just put a turbo on it to start with

 

 

  • Haha 1

Share this post


Link to post
Share on other sites

Hey guys, I have an exhaust that I need to  build for a early LS1 5.0 I think it is. It needs to have a y-pipe off the headers for it to go into to a single exhaust. What size should it be after the y-pipe? 3” plenty big enough? I assume a single resonator and then a straight through styled muffler at the back would be best. Any recommendations on a decent resonator and muffler to use? Don’t want it too loud but can still be a bit noisy. 

Cheers

Share this post


Link to post
Share on other sites
6 hours ago, _Matt said:

Hey guys, I have an exhaust that I need to  build for a early LS1 5.0 I think it is. It needs to have a y-pipe off the headers for it to go into to a single exhaust. What size should it be after the y-pipe? 3” plenty big enough? I assume a single resonator and then a straight through styled muffler at the back would be best. Any recommendations on a decent resonator and muffler to use? Don’t want it too loud but can still be a bit noisy. 

Cheers

Is performance important? I think a single 3" is far too small for an LS1, but it'll be OK if it's just a cruiser. AdrenalinR make the best mufflers, but if you can wait for USA shipping, Vibrant is a good option. 

  • Like 1

Share this post


Link to post
Share on other sites
3 hours ago, Truenotch said:

Is performance important? I think a single 3" is far too small for an LS1, but it'll be OK if it's just a cruiser. AdrenalinR make the best mufflers, but if you can wait for USA shipping, Vibrant is a good option. 

I don’t think performance is that important. He did say it was somewhere around 150kw or something haha 

Have looked at a few mufflers but they’re all really expensive for something that looks alright or just looks terrible for cheaper. So really contemplating making my own like I usually do!

  • Like 1

Share this post


Link to post
Share on other sites
On 13/02/2019 at 19:32, Bling said:

Fibreglass or stainless steel packed reso? Cheers

IIRC @kpr was using a combination of both materials when making his mufflers. In the industry, the good mufflers seem to have multiple layers of different material. This is from the AdrenalinR website: 

  • Every single muffler we fabricate utilizes our 3 stage sound absorbtion methodology which consists of tightly wrapping the baffle in exhaust grade stainless steel wool, ceramic matting and a layer of tightly woven needlemat fibreglass blanket.
  • The stainless wool breaks up soundwaves and creates a barrier preventing the packing from breaking up and exiting the rear of the vehicle prolonging the life of each and every muffler.
  • The ceramic matting absorbs noise and heat preventing the fibreglass turning back to glass.
  • The needlemat fibreglass blanket acts as the final noise insulator which results in quieter, deeper notes singing from the rear of your vehicle.
  • Like 2

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.