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Best Exhaust for a 991.2 GT3

 
Old 12-12-2017, 12:28 AM
  #166  
disden
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Originally Posted by CAlexio View Post
Big difference?... more growl as most say, or anything else of note?
in my opinion a big difference. Definitely more growl, louder, a lower bassy growl which is especially noticeable at lower rpms. Iíd been struggling with this car, it just needed something....this bypass exhaust nailed it. Iíve been giggling all day driving around. I couldnít say that yesterday, other then just happy to be shifting again.
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Old 12-12-2017, 12:35 AM
  #167  
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^ I may try a GRP in the Spring after Winter storage. I believe the tips are 100 mm which is perfect.
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Old 12-12-2017, 12:42 AM
  #168  
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Originally Posted by Jimmy-D
^ I may try a GRP in the Spring after Winter storage. I believe the tips are 100 mm which is perfect.
Serious question. How is this different from the BBI? Rahal had a BBI on the R before marketing their own. On top of that, they all look identical to the GMG. Are there any differences other than the letters on the top of the tips?
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Old 12-12-2017, 12:47 AM
  #169  
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I will vouch for GRP centre bypass also.

I just had it installed on my 911R.

Only one word is needed to describe the sound.

EPIC

As a bonus, there is no droning from idle to redline.

The bypass saved 13+lbs for those that wonders. And no I don't know how much HP it freed up, don't care. 500HP is plenty enough, the nice sound more than make up even if it loses HP.

Oh, and since the factory valve still works, there is a 'quiet' mode. But in Sports mode, after 3500rpm when the valve opens, all hell breaks loose.
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Old 12-12-2017, 01:31 AM
  #170  
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Originally Posted by ranger22 View Post
Serious question. How is this different from the BBI? Rahal had a BBI on the R before marketing their own. On top of that, they all look identical to the GMG. Are there any differences other than the letters on the top of the tips?
BBI makes the exhaust for GR. Their design is near identical to the GMG, both 100 mm tips. With that said GMG bypass has been out 10 years, so nothing new with BBI/GR.
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Old 12-12-2017, 01:34 AM
  #171  
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Originally Posted by 0to60 View Post


BBI makes the exhaust for GR. Their design is near identical to the GMG, both 100 mm tips. With that said GMG bypass has been out 10 years, so nothing new with BBI/GR.
This has been beaten to death. The BBI/GR is different because rhe pipes connect like an X-pipe. GMG and Sharkwerks connect by a rear pipe. They so not sound the same. So yes, it is something new.
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Old 12-12-2017, 01:53 AM
  #172  
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Originally Posted by drdonger
This has been beaten to death. The BBI/GR is different because rhe pipes connect like an X-pipe. GMG and Sharkwerks connect by a rear pipe. They so not sound the same. So yes, it is something new.
Thank you for the info!

X-pipe? I think not. The sides that are X'd come from the same side of the motor. No vacuum there! They may be x'd, but don't expect any scavenging. The rear pipe on the GMG looks like a half-hazard Helmholtz chamber. No idea if it works. 100% sue the BBI and Rahal do not replicate an actual x-pipe. RSS offers a true X-pipe.
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Old 12-12-2017, 03:28 AM
  #173  
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Originally Posted by ranger22 View Post
Thank you for the info!

X-pipe? I think not. The sides that are X'd come from the same side of the motor. No vacuum there! They may be x'd, but don't expect any scavenging. The rear pipe on the GMG looks like a half-hazard Helmholtz chamber. No idea if it works. 100% sue the BBI and Rahal do not replicate an actual x-pipe. RSS offers a true X-pipe.

BBI/GR have a very similar design except the lst part of the tail pipes are separate.
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Old 12-12-2017, 04:04 AM
  #174  
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I currently have a center muffler bypass made by Soul performance. In terms of value - you really can't beat it. I didn't want to spend too much on a center muffler bypass since my main objective is to get aftermarket headers. Soul is a relatively newer company and as such, they don't yet have any other modifications for the 991 GT3. I think there's a side muffler bypass in the works, and maybe headers if there's enough demand.

Anywho - I'm happy with mine for now the sound is great and it feels like it really woke up the GT3 in terms of volume. Lower in the RPM - you can't really hear much except at idle. 4k+/higher in the RPM - sounds great. For the price, it's very difficult to beat, especially in tandem with various tip options that they offer.

Here's a POV video I made with GoPro audio after recording a cold start. It isn't the best audio quality, but you get a decent idea of how it sounds inside the cabin:


And here's a clip that Soul recorded when I visited them:


Truth be told - I'm after some more volume and a more "exotic" sound. Straight piping the exhaust system after the cats will make the car drone pretty badly from what I gather, but I may do it for fun and then just put the OEM side mufflers back if it's that bad. After the winter season is over, I'm looking to install Dundon's race headers along with their muffler. After a lengthy discussion with Jamie and a quick glance on these forums to gauge Dundon's reputation, it's evident that their product is very well engineered and they stand by it.
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Old 12-12-2017, 05:21 AM
  #175  
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Heres a little clip of my car with Dundon Headers + Side Cat Delete..

https://drive.google.com/file/d/1Bv0...ew?usp=sharing
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Old 12-12-2017, 08:05 AM
  #176  
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I’ve had the Dundon race headers on my 2014 for a couple years, the sound is hard to describe adaquately! Dundon service is beyond impeccable.

The only downside to the race headers other than a lot of great sound (too loud for wife/dinner but no drone) is the rich smell of fuel due to cat removal. It’s bad enough that I am trading my race headers for street version with cats (also Dundon, they are so solid I would never even consider a different vendor for exhaust).
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Old 12-12-2017, 11:12 AM
  #177  
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Originally Posted by Hashlak View Post
Heres a little clip of my car with Dundon Headers + Side Cat Delete..

https://drive.google.com/file/d/1Bv0...ew?usp=sharing
I have heard the Dundon system live and I really think it is apples and oranges to comparing to just the center section delete. The car sounds totally different and for me WAY TO obnoxious with the side muffler delete. To each his own and that is what some people want.

I just think there is no comparison between a full system and a center section only. You want full race car sound get a side muffler delete system. You want something that in low RPM sounds stock and you can still have a conversation but when the time is right rev her up and sound killer then you need to go with just a center section.
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Old 12-12-2017, 12:11 PM
  #178  
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I still think IPE catback is still the best way to go. You get side deletes and a valved rear exhaust. This lets you essentially turn the exhaust off when you want it quiet, just like oem.The titanium system is also light and removes heat from the rear tires. The center section has an x-pipe design for that incredible high pitched sound and their quality has gotten a lot better. I will be a guinea pig and test out their titanium carback, when my car comes. Iíll weigh it against the stock and also try to get a dyno done. I have attached a couple of pics. You can see the welds and build quality of the new titanium exhausts are way better than the initial ones.

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Old 12-12-2017, 12:18 PM
  #179  
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Originally Posted by drdonger View Post


I still think IPE catback is still the best way to go. You get side deletes and a valved rear exhaust. This lets you essentially turn the exhaust off when you want it quiet, just like oem.The titanium system is also light and removes heat from the rear tires. The center section has an x-pipe design for that incredible high pitched sound and their quality has gotten a lot better. I will be a guinea pig and test out their titanium carback, when my car comes. Iíll weigh it against the stock and also try to get a dyno done. I have attached a couple of pics. You can see the welds and build quality of the new titanium exhausts are way better than the initial ones.

I would like to see how this exhaust looks after a year. Not implying any thing but would be interested if it is up for the task
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Old 12-12-2017, 12:28 PM
  #180  
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I actually don't understand why most install a center muffler bypass(which they are all about the same design/quality) over a long tube header system with valved SMBP. Is it the price difference only?, because the LTH setup makes more power, reduces a lot of weight, and eliminates a lot of heat near the tires/engine area, plus sounds better(imo) or about the same/similar sound if you go with the catted systems. The center muffler delete systems might make a little(barely any) more power, but in reality the only thing it does it make the engine sound better. For me, I would rather make more power and sound good than just sound good, especially for the money we are spending on any of these settups. Just my opinion but was curious as why most choose the center muffler bypass over other systems.
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