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Side Muffler By Pass Install [PICS]

 
Old 04-28-2019, 04:00 AM
  #16  
goldberg
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Originally Posted by bli8 View Post
I just did the side muffler (Fabspeed) install also. Took me about 7 hours also with the rear tires hanging down while rear of car on jacks.
The sound is louder but I don't feel any drone. It's loudest from mid 2K RPM to 3K RPM, after that the system quiets down and makes cruising and carrying on a quiet conversation a non issue. Again no drone at any speed.
I don't have any sound clips just on the exhaust but someone taped this using my phone earlier today. Car had only 400 miles so I short shifted. Once I get to 1000 miles, I'll be able to track this car properly and open him up and hear him (this one is not a her) sing.

Forgot to mention, once the side mufflers are replaces, they leave behind a gaping hole behind the rear tire on each side of the car and I bet lots of mud and crap will get thrown back into the engine bay and may even corrode whatever is back there. Does anyone make some kind of a close out panel to cover the openings?
Yes, the gaping hole is massive.

Yes, but did you only do Side deletes, and retained the OEM centre?
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Old 04-28-2019, 04:03 AM
  #17  
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Originally Posted by 1963SWC View Post
That's a great looking system but, you are correct in stating that side bypass + center bypass is loud. I cobbled together a similar system using a FVD side bypass and GRP center bypass. I had the center bypass on first (valves disconnected) and really liked the sound but wanted it 10% louder. Added the side bypass and it became 40% louder (seemed too loud to sneak out of my neighborhood or go through any drive-thru) and I also got some sort of vibration/buzz around 2K RPM that was very annoying. So I have moved to side bypass + factory center muffler and it's about the same as factory side mufflers + GRP center bypass. After just a few weeks, I am longing for that increased sound again so maybe I will try to chase down the vibration/buzz........
Keep us posted as to what you end up running. (It is fun trying variations though and once you put on/take off a few times, the process becomes quick and easy)
Wow, do you have tried nearly all the variations of exhaust options. Swapping this 'n that.
I will run this for a while, and see how i go.
It would be hard to go back to a quieter sound. The WOT i really really love this sound.
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Old 04-28-2019, 10:57 AM
  #18  
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Originally Posted by bli8 View Post
I just did the side muffler (Fabspeed) install also. Took me about 7 hours also with the rear tires hanging down while rear of car on jacks.
The sound is louder but I don't feel any drone. It's loudest from mid 2K RPM to 3K RPM, after that the system quiets down and makes cruising and carrying on a quiet conversation a non issue. Again no drone at any speed.
I don't have any sound clips just on the exhaust but someone taped this using my phone earlier today. Car had only 400 miles so I short shifted. Once I get to 1000 miles, I'll be able to track this car properly and open him up and hear him (this one is not a her) sing.

https://youtu.be/9pVkPBhGwK0

Forgot to mention, once the side mufflers are replaces, they leave behind a gaping hole behind the rear tire on each side of the car and I bet lots of mud and crap will get thrown back into the engine bay and may even corrode whatever is back there. Does anyone make some kind of a close out panel to cover the openings?

Car sounds great, doesn't seem to be too loud? ... it's exactly what I wanted to do, side delete and retain the stock Ti centre muffler.

From what I have read, is the stock Ti centre muffler will not last, apparently the forward facing side will buckle and break open, causing the exhaust to leak, damaging the wiring and parts surrounding that area?

Fabspeed came up with a plate that reenforces the weak area, there is YouTube video showing it.

On the fence on what do with the exhaust, want to save as much weight as possible, and definitely don't want it too loud for around town driving.

Any thoughts would be appreciated?
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Old 04-28-2019, 12:42 PM
  #19  
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I've been wondering about aero. No side mufflers does leave that giant cavern behind rear wheels. And removing center exhaust also affects aero to some degree since the muffler serves as an underbody surface to complete the totally flat topography behind the diffuser. Removing both must affect aero to some degree. Something a manufacturer like Porsche has no doubt tested, but small tuner shops welding pipes together to sound cool probably don't think about all that much.

Does the benefit of weight savings and potential heat-soak reduction to the rear wheels outweigh the cons: loss of power and potential affect on aerodynamics?
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Old 04-28-2019, 12:49 PM
  #20  
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Originally Posted by bli8 View Post
The sound is louder but I don't feel any drone. It's loudest from mid 2K RPM to 3K RPM, after that the system quiets down and makes cruising and carrying on a quiet conversation a non issue.
2K ľ 3K and flaps are still closed. Flaps open just before 4K and should get much louder at that point, no?

Sounds similar to stock, I think? Maybe a little raspier?

Compare that to a center bypass:

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Old 04-28-2019, 01:02 PM
  #21  
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Originally Posted by FourT6and2 View Post
I've been wondering about aero. No side mufflers does leave that giant cavern behind rear wheels. And removing center exhaust also affects aero to some degree since the muffler serves as an underbody surface to complete the totally flat topography behind the diffuser. Removing both must affect aero to some degree. Something a manufacturer like Porsche has no doubt tested, but small tuner shops welding pipes together to sound cool probably don't think about all that much.

Does the benefit of weight savings and potential heat-soak reduction to the rear wheels outweigh the cons: loss of power and potential affect on aerodynamics?
Could cause some lift in the rear, on the bottom of the car, every thing covered... they all use completely covered flat bottoms and diffusers, to prevent any air from getting stuck causing lift.

Wonder what the Manthey GT2 RS has done back there?
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Old 04-28-2019, 01:07 PM
  #22  
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Originally Posted by FourT6and2 View Post
I've been wondering about aero. No side mufflers does leave that giant cavern behind rear wheels. And removing center exhaust also affects aero to some degree since the muffler serves as an underbody surface to complete the totally flat topography behind the diffuser. Removing both must affect aero to some degree. Something a manufacturer like Porsche has no doubt tested, but small tuner shops welding pipes together to sound cool probably don't think about all that much.

Does the benefit of weight savings and potential heat-soak reduction to the rear wheels outweigh the cons: loss of power and potential affect on aerodynamics?
You raise a very interesting point.
I think this is more of a problem with the side mufflers removed.
They weight ALOT. And there really is a massive massive cavern where they were.
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Old 04-28-2019, 01:17 PM
  #23  
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Originally Posted by goldberg View Post
You raise a very interesting point.
I think this is more of a problem with the side mufflers removed.
They weight ALOT. And there really is a massive massive cavern where they were.
I've found over the years... sometimes cars are better stock.
It's fun to mess around and "improve" your car with mods. But you can spend thousands of dollars and in the end you've made your car slower.

I remember a funny Top Gear episode where they compared a stock car with one some guy modified with new suspension coilovers/springs, sway bars, exhaust, intake, etc
Guess what... the stock car was faster around the track lol.

The other point is if someone is faster around a track in the car, stock, compared to yours with mods, then what good are the mods? Other than to make the car sound cool.
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Old 04-28-2019, 01:42 PM
  #24  
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Originally Posted by goldberg View Post
Yes, the gaping hole is massive.

Yes, but did you only do Side deletes, and retained the OEM centre?
I wanted to use the factory Ti center muffler so only did the side delete. Someone needs to fabricate a close out panel to fill the gaping hole so dirt and debris won't get thrown into the engine bay and maybe at the same time, do something to improve airflow into the area.
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Old 04-28-2019, 01:58 PM
  #25  
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Originally Posted by bli8 View Post
I wanted to use the factory Ti center muffler so only did the side delete. Someone needs to fabricate a close out panel to fill the gaping hole so dirt and debris won't get thrown into the engine bay and maybe at the same time, do something to improve airflow into the area.
Totally agree with this.
I wish i was that handy to fab something. Or at least have the tools to do such
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Old 05-06-2019, 08:40 AM
  #26  
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Below are some drive by videos.
BOTH videos are with Valves Closed

Both videos are taking near to redline, but not mashing the peddle. Still rolling on the throttle.

This thing is VERY LOUD. We all know videos / audio doesnt do justice. Have to hear in real life. I will get some more rolling videos soon. Its quite loud in the cabin too.

But the sound now, is like a real exotic supercar sound. Can be heard from a LONG way away.



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Old 05-06-2019, 11:15 AM
  #27  
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Originally Posted by goldberg View Post
Below are some drive by videos.
BOTH videos are with Valves Closed

Both videos are taking near to redline, but not mashing the peddle. Still rolling on the throttle.

This thing is VERY LOUD. We all know videos / audio doesnt do justice. Have to hear in real life. I will get some more rolling videos soon. Its quite loud in the cabin too.

But the sound now, is like a real exotic supercar sound. Can be heard from a LONG way away.



https://youtu.be/-xi7ICjt6-U

https://youtu.be/U-07QCn5srU

Sounds amazing!!
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Old 05-06-2019, 11:42 AM
  #28  
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Now having the Febspeed side bypass w/ valves on the car for 2 weeks and a few hundred miles, I find the exhaust sound level is completely acceptable at cruising, especially once the engine goes over 3K RPM which is 73 MPH in 7th. So cruising is not an issue at all, but I do find car a little too loud for my taste in street driving, even in part throttle. The car sounds fantastic at full throttle and that wail...... So I don't want to go back to stock now and am contemplating putting some sound deadening mats in the back of the car to compensate. So the mats may add 5 pounds, but still a small price to pay for the sound and the overall weight savings.

BTW I read somewhere here that the Ti Center Muffler on the 991.2 RS is heavier than those on the .1 cars, can someone confirm this? I wonder if Porsche beefed up the sidewalls. I love the sound of the Ti muffler so I'd like to keep it as much as possible.
Now on my Touring, if I were to do anything, I'd probably just go for a Center Bypass with some kind of crossover design.
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Old 05-06-2019, 12:45 PM
  #29  
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I just completed my side delete install last Monday and after ~1000 miles at the Smokies event, can say they are an improvement. My butt dyno can't tell any real difference, my ear dyno "feels" like its faster, and my tires appreciated removing the heat sink for the high speeds at Road Atlanta. Even in the afternoon, it didn't seem that the rears got as greasy as previous - but can't say definitively until I try it on a track I have previously been on. It took me ~3.5 hours total in my garage to do the swap. I love the new sounds. I would say it is 25% louder with just the side deletes and nothing else. I feel like 80-90% of the drone is gone.
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Old 05-06-2019, 10:14 PM
  #30  
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I have an appointment with Fabspeed on Monday I currently have a sw center bypass sounds incredible but I want a little louder hopefully removing the side mufflers coupled with the center delete wool sound great! Sw center is smaller then competing companies so hopefully that will keep it from being to loud and retain the high pitch!
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