soulsea

Hi,

Car should be here in a few days ... I'm not going to mod it much but I do want to give it a new exhaust. What I would like is the most aggressive sounding exhaust available. Weight gains are always welcome, but I'm not doing this for HP gains, it really is as shallow as I just want her to sound like she means it. I also have no intention of doing any tuning so this has to be a no tune, no CEL, bolt on solution.

I've started talking to a manufacturer (forum vendor) who are about to release a compatible system, but I also would like to know what are all the existing available options to me. I'm sure this has been addressed before, but please bear with me as this is all very new to me.

So far as I've been able to tell from reading RL threads, the 991 GT3 and 991 GT3 RS are the same exhaust wise ... is this correct? When I see compatibility charts can I assume that anything that works with the GT3 will also work with the RS?

Also from what I gather the RS exhaust system is very very different from the one in my TTS, which has the cats and one big muffler and that's it. It seems the GT3 exhaust has three sets of mufflers ... I'm not sure where they are all located, which ones have sensors that may or may not trigger a CEL, if the cats can be changed to say 100 cel, and how they all work together to manage sound. In short, I have no idea how the GT3 exhaust is set up.

But it does appear that different manufacturers remove either one or two sets of mufflers (side and center) and manage to do so without triggering a CEL. It seems that deleting one set of mufflers also results in a small weight reduction and deleting two sets make a huge weight reduction of around 60lbs. (on a side note I'd be interested to know how such a big weight reduction affects the handling on track and if something needs to be done alignment or suspension wise to counteract this effect)

Aaaanyhoot ... so far I've been able to find the following systems:

http://www.armytrix.com/Porsche-991-GT3.php

http://bbiautosport.com/new/index.ph...exhaust-bypass

http://www.akrapovic.com/#!/car/prod...d=19&yearId=61

http://www.ipe-f1.com/index.php/en-G...sche-991-gt3-2

There's also some fabspeed options as well as the Sharkwerks.

The two SW options are intriguing and I'm trying to figure out the difference between them ... they also seem to reflect the differences in other systems in deleting either one or two sets of mufflers:

http://www.sharkwerks.com/products.php?pid=410
or
http://www.sharkwerks.com/products.php?pid=339

The second SW option seems the most appealing in regards to increasing sound and shedding weight, and at a relatively low cost, so it is my leading candidate, but perhaps there are downsides to this option that I am not aware of.

I'm sure there are other manufacturers as well, so if a worthy one has escaped my attention please point me to them.

Again, my apologies if this has all been mentioned before ... I really do appreciate any help or feedback from those who have gone with any of these exhaust options on their 991 RS.

Thanks.

Jamie@dundonmotorsports

Dundon Motorsports Race Headers, no tune required no check engine light on 2015/2016 (2014 there are a few due to cam related issues...) ... and 25whp max, 20whp peak.

Keeps the valves for quiet around town operation and we have many very happy owners...


Do a quick search for Dundon and you'll find a bunch of threads about our exhausts!

Or shoot me an email jamie@dundonmotorsports dot com

John@Fabspeed

Congratulations on picking up an RS, and keeping it! Not often you hear that nowadays haha. The GT3 and RS do have the same systems, although the RS center muffler is made of titanium. If you are looking for maximum sound, no tuning, no CEL, and the most weight loss it seems you are looking for a Sport Headers (with cats) and Competition Exhaust that eliminates both the side and center mufflers of the car. Here are some photos for reference.






PM heading your way, and I would be happy to answer any questions you have on meeting your goals. Post up some pictures when you have a chance

drdonger

My favorite sounding exhaust is IPE, although most complain about the quality and lack of power gains. If I wanted the best sound I would go with IPE.

For power I would go with Dundon headers. I think everyone is waiting for the sport version with cats.

SDGT3

I have the Sharwerks bypass with the stock tips. It is the least expensive less intrusive way to go. Looks bone stock sounds UNREAL and everything works! Had the same system on my last RS and was pleased with it then also!. If you are looking for an easy way to get a more aggressive sound and leaving you car somewhat Virgin, this is a great option. I am sure other bypasses are good also but I like to leave stock tips on to give it a stock appearance. Good luck anyway you go!

soulsea

Thanks for the feedback ...

Could you perhaps explain to me what the difference is exactly between the SW 'bypass' system and their 'track' system?

Guest89

Track system is mega loud and drones. If you call them and talk to Alex or Dan they'll probably steer you away from the track pipe.

soulsea

You seem familiar.

Thanks, I'll give 'em a call.

Nizer

+1

Based on your criteria this is the way to go. Quick and easy with no hassles (CEL/warranty/emissions) and when the sport valve is activated you're essentially running straight pipes. Lot's of options for these but Sharkwerks and GMG seem to be the favorites.

soulsea

Can you guys educate me on how the valves work?

From what I gather under a certain setting they activate above a certain RPM threshold.

I'm sorry for this basic question but I don't get the car until Wednesday and my only from of reference is my TTS, which not only has a completely different exhaust setup but its sport and suspension modes are also completely different:

On the TTS I have 'Sport' 'Sport Plus' and I don't have an exhaust tip button like the GT3s seem to have. When either in Sport or Sport Plus the ECU artificially makes the exhaust louder and makes it pop without any valves in the exhaust system.

It looks like in the GT3s there's only two modes, regular and Sport, and there seems to be the exhaust tip with that I presume makes it louder by opening the valves independent of which mode one is in. Do I have this right?

Is there a way to keep them open all the time notwithstanding the drive setting?
Or is there an exhaust system that bypasses the valves thus keeping the flow unrestricted at all times?

For example on my Z, the Corsa system removes the valves completely ... once installed the oem valve harnesses/plugs get covered and zip tied to the frame.

JesseRohr

Here's what I am using. I get compliments every time I am out in the car.

You can pick it up retail for less than $800.00.

http://mbrpautomotive.com/?page=products&part=S7607BLK

Dan@SharkWerks

The downsides are it's really loud and throttle response is reduced at low RPMs due to a significant decrease in back pressure (you can remedy this quite a bit with a tune but it's something you said you didn't want, so...). The track exhaust we make is loud all the time other than one quiet spot around 3000 RPMs that's reasonable for freeway driving but I would never recommend an exhaust that removes all the mufflers if you plan to drive around other people, traffic, pedestrians, houses, etc.

The bypass is much more reasonable for daily driving. No drone and you can turn the exhaust on/off with the button so it's nearly stock sounding when you want.

If you want to avoid tuning and CELs, I would highly recommend keeping the original catalytic converters. This is the primary emissions equipment on the car and without it, the super clean GT3 will then stink like a 60s muscle car; not to mention the toxic nature of the fumes you're putting out at that point to everyone around you including yourself/your garage etc. It will also almost certainly cause a check engine light, which will also put the car into a safe mode to protect itself, further causing power loss. If you are only tracking the car and it is not registered for the street, this might be an option to consider.

soulsea

Thanks for the help everyone ...

And especially Dan for patiently answering all my no0b questions over the phone.

lumber

Dan and the gang over at Sharkwerks are the best!

gmgracing

Thank you Mr. Satco!

Soulsea, If you wanted to keep things simple (and not touch the header/cats), just running our center section along with side muffler deletes will yield a 17hp gain while sounding incredible. Here is a link to a recent independent dyno result. Of course we offer our headers as well, it just depends how much you want to modify the car.

If I can help to answer any questions just let me know.