DIY Turbo Discussion greddy on a 1.8? homebrew kit?

Bros op on muff.

Thread Tools
 
Search this Thread
 
Old 07-24-2012, 09:08 AM
  #21  
Elite Member
iTrader: (2)
 
triple88a's Avatar
 
Join Date: Apr 2006
Location: Chicago, IL
Posts: 10,454
Total Cats: 1,799
Default

Whos hacking your exhaust? I hope it's a reputable place or IT WILL RATTLE EVERYWHERE.

On a side note, you might be able to return it on the sellers dime if this is the same listing.

"Magnaflow Stainless Steel 3 inch Oval Muffler is designed to reduce the amount of noise emitted by the exhaust system and to increase engine efficiency. It is manufactured from stainless steel and comes with an oval body of 18 inches with an overall length of 24 inches. This muffler offers a single inlet and outlet measuring 3 inches that is positioned in the center. It features a straight-through perforated stainless steel core as well as an acoustical fiber fill and is backed by lifetime warranty."
triple88a is offline  
Old 07-24-2012, 09:24 AM
  #22  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default

I don't like the one you got. It looks chambered. I didn't even know magnaflow made those, unless for trucks in the XL series.

What part number does the box say?


because this is what yours should look like*:



*the one I posted before has an offset outlet, the above is center/center.
Attached Thumbnails Bros op on muff.-dsc01038.jpg  
Braineack is offline  
Old 07-24-2012, 09:25 AM
  #23  
Elite Member
iTrader: (2)
 
triple88a's Avatar
 
Join Date: Apr 2006
Location: Chicago, IL
Posts: 10,454
Total Cats: 1,799
Default

Originally Posted by Braineack
What part number does the box say?
https://www.miataturbo.net/diy-turbo...63/#post907135

?
triple88a is offline  
Old 07-24-2012, 09:47 AM
  #24  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default

interesting.

This is something unlike most Magnaflow and looks to be a new part:

I have a Magnaflow single 3" with a 12579 muffler mandrel system in the corner for the day TOG headers go in... The 12579 is pretty unique from all the other Magnaflows in the 5x11 case... It is a center 3" inlet that splits off inside to dual 2.5" pipes, and comes back out a single 3" center... Magnaflow designed this muffler especially for the new Vortec V8 trucks due to the bottom end loss, and resonance issues with the 4.8, and 5.3 ... I personally don't think the Flowmaster 70 will flow what the TOG headers can, so a straight through muffler is in order... If you want more info, PM me off the list, and we can talk... There are many guys on this board who consulted me on exhaust, and have come through with flowers... So, take it for what it's worth...
Magnaflow has confirmed, the 12579 muffler was designed for our 5.3L engine. It is louder than stock (by maybe 10-15db's, my best guess), but definitely quieter than the 12589 (by at least 10-15db's). The 12579 has a nice sound, but I doubt you will be able to tell how loud it is to the outside world unless you go WOT in a tunnel or a parking garage or something. I've driven around town with my windows down and I can't really hear it that much. ON THE OTHER HAND, the 12589 has an awesome louder sound that you can definitely hear, especially when you drive under freeway overpasses. It leaves no doubt that you've done a muffler mod to your AV, and it really sounds great (sort of sounds like a cigar speedboat exhaust). From a pure exhaust note standpoint, I'd vote for the 12589 (the AV also sounds less strained under WOT with the 12589, whereas the 12579 is sort of higher pitched and makes other drivers think you're winding up your engine to race or get ahead of them -- a layman's observation).
seems to be a better "muffler"
Braineack is offline  
Old 07-24-2012, 09:48 AM
  #25  
Elite Member
Thread Starter
 
flounder's Avatar
 
Join Date: Mar 2010
Location: Detroit
Posts: 1,524
Total Cats: 31
Default

Damnit. How bad can it be to run this instead? Being a 3" exhaust, I can't imagine even with this small of a restriction, I'll have a problem with backpressure?

I got it off of amazon after searching for 5x11x22 3", Plus someone else on mt.net said they are using this P#.
flounder is offline  
Old 07-24-2012, 09:50 AM
  #26  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default

If I had it, I'd still run it. I don't believe it's going to measureably impact performance over the single core.
Braineack is offline  
Old 07-24-2012, 10:06 AM
  #27  
Elite Member
Thread Starter
 
flounder's Avatar
 
Join Date: Mar 2010
Location: Detroit
Posts: 1,524
Total Cats: 31
Default

Hell, maybe it'll help low end torque? lol
flounder is offline  
Old 07-24-2012, 10:33 AM
  #28  
Elite Member
iTrader: (9)
 
TurboTim's Avatar
 
Join Date: Jun 2006
Location: Chesterfield, NJ
Posts: 6,893
Total Cats: 399
Default

I predict your friend at the exhaust shop will use crush bent pipes to make your exhaust. The tightness of the bends required to fit that huge muffler back there will mean the inside of the pipe is pretty tiny after it is crushed, so the muffler won't be your problem. I'd say it'd flow about the same as a 2.5" system orientated the same way.

I go with the 5x8x18 muffler. Plenty quiet and the muffler fits at an angle so the bends are much straighter, especially if you are not using mandrel bends.





Now if my new setup is too loud or drone-y, then I will definitely consider that 'new' magnaflow, I had no idea they made something like that. Of course, with tight radius mandrel sections. The old Edelbrock stainless mufflers were designed like that and I searched for a while for them back when I made my exhaust but are no longer made.

EDIT: I use 18" long muffler, not 14.
Attached Thumbnails Bros op on muff.-msmexhaust1.jpg   Bros op on muff.-msmexhaust2.jpg  

Last edited by TurboTim; 07-24-2012 at 12:44 PM.
TurboTim is offline  
Old 07-24-2012, 10:56 AM
  #29  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default

you can fit the 5x11x22 in the same fashion as above. in fact, I'd prefer that over mine with my crazy ? bend.


I just cant remember who did it to post pics.
Braineack is offline  
Old 07-24-2012, 11:06 AM
  #30  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,821
Total Cats: 3,481
Default

Oh wow, so this could potentially be a BETTER solution for people that want max flow with minimal sound? Since its still technically "straight through" I don't see it choking up too much more than the original, but I may be way wrong.
I know on the Borla Hush for the scoobs, it goes from 3" in to 2 2.5" outs and is a bit more restrictive than your average straight through 3", but I'd gladly give up 5-10hp for a SUPER quiet exhaust.

Is there a cutout/diagram of this new one?




*EDIT: just saw the uploaded pics
Definitely looks like it will be significantly more restrictive.
I'd still run it though. Looks like it will be ultra quiet.
18psi is offline  
Old 07-24-2012, 11:08 AM
  #31  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default

Pics pretty much show everything you need.

3" pipe splits to (2) 2.5" preferated cores, then back to a 3" outlet. I'm sure it can flow more CFM than you can afford.
Braineack is offline  
Old 07-24-2012, 11:10 AM
  #32  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,821
Total Cats: 3,481
Default

see edit

I was really hoping it would be a smooth Y transition instead of a T
poop
18psi is offline  
Old 07-24-2012, 11:20 AM
  #33  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default

I would too, but I doubt it matters.
Braineack is offline  
Old 07-24-2012, 12:47 PM
  #34  
Elite Member
iTrader: (9)
 
TurboTim's Avatar
 
Join Date: Jun 2006
Location: Chesterfield, NJ
Posts: 6,893
Total Cats: 399
Default

Originally Posted by 18psi

Is there a cutout/diagram of this new one?




*EDIT: just saw the uploaded pics
Definitely looks like it will be significantly more restrictive.
I'd still run it though. Looks like it will be ultra quiet.
Originally Posted by 18psi
see edit

I was really hoping it would be a smooth Y transition instead of a T
poop
Pic showing it is a T instead of a smooth Y?
TurboTim is offline  
Old 07-24-2012, 12:49 PM
  #35  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default

I'd settle with unsmooth Y.

Attached Thumbnails Bros op on muff.-12579.jpg  
Braineack is offline  
Old 07-24-2012, 12:55 PM
  #36  
Elite Member
iTrader: (9)
 
TurboTim's Avatar
 
Join Date: Jun 2006
Location: Chesterfield, NJ
Posts: 6,893
Total Cats: 399
Default

Ahh ok, not really a "T" but poor manufacturing of the Y. Yeah, i'd say that's maybe 3 hp.
TurboTim is offline  
Old 07-24-2012, 01:03 PM
  #37  
Elite Member
iTrader: (2)
 
triple88a's Avatar
 
Join Date: Apr 2006
Location: Chicago, IL
Posts: 10,454
Total Cats: 1,799
Default

U sure it looks like that or its not a square split?

Y U NO RUN FLOWMASTER 40?
triple88a is offline  
Old 07-24-2012, 01:05 PM
  #38  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,821
Total Cats: 3,481
Default

When you get this sucker on there, we need GOOD SOUND CLIPS. Seriously. Please don't let us down.
18psi is offline  
Old 07-24-2012, 01:07 PM
  #39  
Elite Member
iTrader: (2)
 
triple88a's Avatar
 
Join Date: Apr 2006
Location: Chicago, IL
Posts: 10,454
Total Cats: 1,799
Default

This good for ya?

triple88a is offline  
Old 07-24-2012, 01:08 PM
  #40  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
Default

Originally Posted by triple88a
U sure it looks like that or its not a square split?

Y U NO RUN FLOWMASTER 40?
look at the preforations, it definitely angles out. Also you can see the "wall" is smoothly formed, where it forms a slight V.

flowmaster 40 :




chambered mufflers don't use perforations and sound-deadening material. The use noise-canceling tech.
Attached Thumbnails Bros op on muff.-flowmaster-40-series-mufflers-1.jpg  
Braineack is offline  


Quick Reply: Bros op on muff.



All times are GMT -4. The time now is 05:35 PM.