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Exhaust options?

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Old 10-21-2011, 05:19 AM
  #16  
porsche_968
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Weird. I mentioned I wasn't sure if I can mention vendors on this forum. Then three other posts mentioned the vendor so I thought we can mention vendors. No idea why this vendor is banned
and not others.

Moving on, the pass through muffler is a round tube and I was told by the shop that they can put longer ones on to quiet the sound if I prefer. I was looking fo r weight loss, so the deeper sound is a bonus.
Old 10-21-2011, 10:21 AM
  #17  
tek_121
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Cant find the post you're talking about...

Originally Posted by wpb968
I recall a post by Odurandina on this forum a few months ago. He replaced the enitre cat back with an aftermarket resonator and muffler. He liked the result and saved a lot of weight and cash. He had specific manufature/model numbrs in his post, He brought his parts to a muffler shop and had it welded up. He is easy to find on this forum and will be glad to give the info you are looking for.
Old 10-21-2011, 10:24 AM
  #18  
tek_121
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So you mean round like that, and a center/center specs?
http://www.borla.com/products/produc...?cat=2&type=88

Originally Posted by porsche_968
Weird. I mentioned I wasn't sure if I can mention vendors on this forum. Then three other posts mentioned the vendor so I thought we can mention vendors. No idea why this vendor is banned
and not others.

Moving on, the pass through muffler is a round tube and I was told by the shop that they can put longer ones on to quiet the sound if I prefer. I was looking fo r weight loss, so the deeper sound is a bonus.
Old 10-21-2011, 02:59 PM
  #19  
Fox944
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RS Barn, B&B Tri-Flo, Cargraphic all make cat backs for the 968. There are others as well. based on 1st & 2nd hand experiance, the B&B system sounds best if you are getting just a cat-back. The RS barn system has a slightly better power curve...although niether will gain you more then a couple BHP up top....and most systems will lose some midrange power.

Tri-Flo system is espensive, but very high quality. If you do get their system...make sure you specify that you want the 2.5" cat back and not the 3". The 3" is too big and is only good for turbo applications, otherwise you will lose too much back pressure and power.

I had RS Barn's full system (including header) on my car. But my fav sounding 968 is cosmo's car before he went with an F/I set up. He had a 2.5" B&B tri-flo cat back.
Old 10-21-2011, 05:51 PM
  #20  
sydneyman
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Originally Posted by Fox944
RS Barn, B&B Tri-Flo, Cargraphic all make cat backs for the 968. There are others as well. based on 1st & 2nd hand experiance, the B&B system sounds best if you are getting just a cat-back. The RS barn system has a slightly better power curve...although niether will gain you more then a couple BHP up top....and most systems will lose some midrange power.

Tri-Flo system is espensive, but very high quality. If you do get their system...make sure you specify that you want the 2.5" cat back and not the 3". The 3" is too big and is only good for turbo applications, otherwise you will lose too much back pressure and power.

I had RS Barn's full system (including header) on my car. But my fav sounding 968 is cosmo's car before he went with an F/I set up. He had a 2.5" B&B tri-flo cat back.
Fox, what would you say is the main difference between the two sounds? I was looking at the RSBarn catback but am considering others as well. I already have the Stahl header...
Old 10-22-2011, 07:26 AM
  #21  
savvas944
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Perssonal experience on 2 nos 968,you loose mid range torque.
Old 10-27-2011, 11:40 PM
  #22  
notthd
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This is going to sound nuts but once upon a time - going only for a better sound and ditch the heavy muffler - I made a custom one using 4" polished truck exhaust tubing tapered down and welded up at the muffler attachment point. I tacked a hanger and it looked great. Here is where is gets good. I used an offshore racing marine baffle. They make 2 kinds, marina and offshore. They are slip ins with lock tabs. Could swap out for sound or run open. The offshore baffle sounded fantastic and did not effect torque as best as I could tell. under $250

Back to reality.. Cheers, Mike
Old 12-13-2011, 06:33 PM
  #23  
odurandina
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i like the idea of aftermarket exhausts and stainless steel pipe, but i am yet to hear anything good... what i have heard are some pretty crappy setups on the interwebs, and of course in real life. moreover these kits are expensive. they usually have one really nice part; (the s-pipe). but any good exhaust man can handle this part of the job.



letting loose a truly exotic 4 cylinder engine....


sorry about another self-serving post about my exhaust but, here it is;

no more taint, stock sound... no more mad, loud lawnmower sound. no turbo whine (which of course, isn't a bad thing)... no more just plain too loud anymore, at least not until you really step on it... NO RICER GAGBURBLE like ALL the aftermarket exhausts; if you had a Ferrari 360 for a week, you'd be given to the temptation of reving the f_ck out of it everywhere you go -----

well, it happened to me !! i love my car ! i admit it. i'm a full on JUNKIE !!...... i tried doing straight pipes with the Hooker glasspack, but the first inclination was a too loud and too rough... i had originally bought this nice resonator but never bothered to add it with the original test pipe... if you're planning on doing something with your exhaust anytime soon, build this ! so wtf happened ? --- by adding just the odd MUSTANG resonator (not a glasspack, but just a hollow tube chamber that opens from 2 1/2" to 4" and back to 2 1/2") -- well, this thing made a huge difference....

it's makes a low, "throaty" sound at idle, similar to a big V6, but when you get on the throttle it begins to turn a deeper "roar," and finally, at full throttle, it sounds like no 4 cylinder engine you've never heard before... not quite like running straight pipes, nor a V6, nor V8.... but really good for a 4 cylinder. i've searched the webs for any combination that can make a sound like this and nothing even comes close....



somewhere along the way, somebody convinced us all to accept what isn't so.


the variocam is a huge 4 cylinder engine that breathes very large volumes of air by 4 cylinder engine standards....

so why do none of the exhuasts on youtube allow the 3.0 litre engine to sound like a 3.0 litre engine ?

furthermore, all the 968 catback systems desperately need resonators. watch the videos. they sound a bit less 'ricey' than Honda's but they all still sound like crapola.... if you're running an old cat (or any cat), stock or aftermarket exhaust, they all sound basically the same; like pee-shooter fart cans with about 2 point nuthin' litres of displacement. why ? i believe it's mostly due to the fact that once the variocam kicks on, you've got a mild race engine. and after that point there's no benefit to having a catalytic converter in the circuit.

but, stand next to this car at idle, and give it a little throttle.... it sounds more like 4.0 litres. rev it up to 4,500 and then let off the gas and it makes a fat, low-frequency crackle... then rev it toward the limiter. heaven.



1st good exhaust;

i tried several combinations before finally combining a Hooker Maxflow glasspack with an SLP loudmouth hollow chamber resonator... about a year later, i killed that muffler when i tried to drive across some dirt going too fast and bottomed out (long story)... it was too loud anyway -- so i changed to a larger 22"X11"X5" Magnaflow glasspack with one mild 'S' bend inside just before leaving Florida last spring.

had a beautiful pipe made up to accommodate the larger muffler..... the key is the resonator' an SLP 2.5"/4"/2.5" X 18" which gives the engine a really throaty sound at low rpms and it changes to a more and more exotic sound at higher rpms. the setup is completely open but the larger muffler has removed 75 % of the loudness factor and left just a right amount behind. still, the sound when you let off the gas is sick. i promise none of the cat back systems sound anything like this..... the resonator is located just behind where the cat used to be.... some of the other hollow resonators have partial cutouts inside. but this is completly hollow with no internal parts whatsoever. the muffler is extremely large (12589), and barely almost doesn't fit.

http://www.summitracing.com/parts/SL...3919/?rtype=10




Originally Posted by Butters944

Uh is this kind of setup illegal?

well, i know some cities in the desert southwest like Albuquerque and Phoenix, they have horrible air stagnation and smog. in Massachusetts we don't have any such problems and as such, we have no visual exhaust inspection or smog check after 15 years. i hope things stay that way. i can go to the most **** inspection center w/ no worries.


Carl (928 forums) drove it last summer.

Originally Posted by Ispeed

I got to drive this car last night, so I will give my report on the sound....

has a big deep sound, and It sounds to me like a tweaked 911 six cylinder sound. It's good stuff....







this experience has taught me something about what a normally aspirated 4 cylinder can do as far as the exhaust note. but, the four cylinder architecture is the limiting factor... in the end, flat 6's w/ turbos, v8's, v10's and v12's all sound better... but this combo makes way better sound than other exhausts, and costs much less to put on the car. i would recommend my setup starting with at least an 18" X 9" Magnaflow stainless steel glasspack... and don't forget to run a heavy guage pipe and use all three mounting points.




/
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Last edited by odurandina; 01-12-2012 at 04:29 PM.
Old 12-14-2011, 10:40 PM
  #24  
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If they are tuned right they can sound great. The best 4 cylinder exhaust note IMO is a V-max with 4 into 1 straight pipe
Old 12-15-2011, 10:01 AM
  #25  
RajDatta
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http://broadfootracing.com/944___968_exhaust.htm

Another option. Not sure how it works, but it sure looks nice. They know their stuff.
Old 12-15-2011, 12:11 PM
  #26  
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I modded my stock resonator, there is a plate on the engine side of the resonator that is very restrictive. Not making big HP claims but with the plate removed (royal PITA) the car was noticeably more responsive. A few others have done the mod and found the same improvement.



Old 12-15-2011, 04:18 PM
  #27  
odurandina
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sorry for forgetting to mention.... awesome pics.

the stock, 12 ton hunk of rust-resistant steel does accomplish 1 thing. it tames the massive variocam and makes the car feel like a production car. too bad it does rob significant power.... this isn't an audi and was never supposed to be.
Old 12-15-2011, 04:48 PM
  #28  
Damian in NJ
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Originally Posted by porsche_968
Weird. I mentioned I wasn't sure if I can mention vendors on this forum. Then three other posts mentioned the vendor so I thought we can mention vendors. No idea why this vendor is banned
and not others.

Moving on, the pass through muffler is a round tube and I was told by the shop that they can put longer ones on to quiet the sound if I prefer. I was looking fo r weight loss, so the deeper sound is a bonus.
Vendors get banned for shilling their products without becoming a Rennlist sponsor usually.
Old 12-15-2011, 06:40 PM
  #29  
SDDave
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Any chance we can keep on-topic and not respond to 56-day old posts to stir up the typical drama? Thanks.

Odurandina- what would you estimate the all-in cost of your setup is?

Orphan- what all was involved (tools, time, etc) in removing that plate?


Dave
Old 12-15-2011, 07:05 PM
  #30  
Orphanowner
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First off, I've been doing this thing a long time...used to be on here as Wynnclaims. Just reactivated my account, with the new name.

On to the exhaust....to knock out the plate is a royal PITA. I used a air chisel and a torch. Basically you punch it, reach in with channel locks, and remove material and repeat. I think I used the torch to burn the plate a bit to break it up in smaller pieces. I'll post pics from the episode as I find them

This resonator mod with a straight pipe in place of the cat was worth 8 hp on a dynojet with one of my chips and some intake mods. There is a thread on another forum from like 2005 with all the details.

The whole purpose of the plate was to keep the db's down to pass USA noise limits. It was also responsible for the flat spot that most attribute to the Varicam. The chambered resonator does not flow so poorly until they put the plate in the first chamber. I'll put a pic up with the diagram of the chambers. Note the intense heat caused by the first chamber's blocking plate.

As we know, a big 16 valve 4 banger is notoriously loud. With the mod I did, it was acceptably louder without any of the droning that you get from from most aftermarket or cobbled up exhausts. I like stealth.




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