bogey1

I am looking for a little help regarding exhaust for a new-to-me 997.2 GT3. I want to upgrade the exhaust but have two limiting factors: the car has a CPO warranty and I don't want to void it with required Tuning, and I live in Atlanta so it needs to pass emissions. Its not a track car. Looking for improved sound without the loss of power.
I am a bit confused about the posts I have read about deleting the side mufflers? Is this the route to go and then who makes a great center muffler / tips? Or do I leave the side mufflers and just buy a new center? It would seem to me getting rid of the side mufflers would be a great idea to reduce weight and maybe temperatures back there? But I don't want to lose a bunch of power or torque by messing with up an already optimized system.

Any thoughts for an enthusiastic new GT3 owner (but long time Member) would be greatly appreciated.

skxf430

Just do a center pipe delete. Sharkwerks and GMG have some good pipes.

boostedt0y

There are a couple options available now for an exhaust. The first and the most common is the center bypass which removes the center muffler but retains the heavy OEM side muffler. Sharkwerks, GMG, and RSS make center bypasses.

Another option is to do a side muffler delete system in combination with the OEM center muffler system. This setup reduces about 40 lbs or so from the rear since it replaces the side mufflers and reduces the heat that is exposed to the rear wheels. One downside is you lose the exhaust valves in most of the side muffler delete systems such as the one provided by BBI or FVD. I think TPC makes a side muffler delete that uses a valving system similar to the OEM side muffler bypass. The side muffler delete system is also quieter than the center bypass from a car I heard that has the side muffler delete installed.

The above options will not really provide any increase in HP and if any very minimal. I didn't have any warranty issues with the bypass on my car, but that may be dealer to dealer specific as my local dealer is generally mod friendly to some extent. Also, you don't need a tune for a bypass.

The third option is to do the Dundon race headers that replaces the stock headers, cats, and side mufflers and retains the OEM center muffler. This system is advertised as making more power over stock without a tune (I think they claim 25rwhp), but is pretty costly ($6-7k?). This system may void your warranty, but you'd have to double check with your dealer.

HRE_Jurrian

Both the Slip-On and Sports Cup system are available for your 997.2 GT3. If you're looking for the best and nothing else will do, then this would be a great start. Here's some more info:

Akrapovič Slip-On System
The Akrapovič Slip-On system is based on the same layout as the original exhaust system of the GT3 with valve control. The Slip-On contains a titanium muffler with two double round tailpipes. The muffler is easily installed on the original exhaust system. The Akrapovič Slip-On makes the GT3 more powerful and lighter, even though the exhaust system is not replaced entirely. The sound of its six-valve engine is also noticeably improved. The Slip-On exhaust system offers weight reduction in the rear of the Porsche and an increase in power. Two tailpipes, 100 mm in diameter, make it clear that the Akrapovič Slip-On system is no ordinary exhaust. The unique look is completed with a mandatory rear carbon fiber lip (not applicable to the 3.6L).



Technical Data and Information For Slip-On System




Akrapovič Sports Cup System
The Akrapovič Sports Cup exhaust system is based on the Porsche Sports Cup rules, which state that the original exhaust manifold with integrated catalytic convertors must be retained. We therefore developed a performance and weight-optimized titanium end muffler with appropriate link pipes as the connecting piece to the manifold. This kind of construction reduces the weight dramatically in comparison to the original exhaust system. The weight distribution of the vehicle is improved considerably because of the weight reduction in the area behind the engine and the rear axle, which has an extremely positive effect on the handling.

When installing Akrapovič aftermarket optional link pipes with sports catalytic converters or without catalytic converters, which are developed for use on closed tracks only, remapping the ECU is mandatory. When installing Akrapovič aftermarket exhaust system that was developed for use on closed tracks, we recommend remapping the ECU in order to prevent potential »check engine light« warning signals.



Technical Data and Information for Sports Cup System

John D II

We produce a great center muffler delete option and we offer Rennlist member discounts. You can view it, along with videos on our web site...message me if you have any questions, I will be glad to help.

997s07

I would go with Cargraphic. The un-silenced version. Incredible sound but not obnoxious. The quality is what you would expect from a German company. The tips are welded to the delete pipe, it looks like an RSR set up from up close.

bogey1

Thank you everyone. Great explanations and suggestions.

FJSeattle

This is a great way to see all the vendors trip all over themselves to sell an exhaust system....

Rick GT3

what about some NoIsE!!!, just complete muffler delete(side & center). I have my GT3, like this (TPC & Sharkwerks), yes is LOUD, but really like it a LOT!!!

JB911

Start with the center delete-there's someone selling the Carnewel remote so you can control the valves:
https://rennlist.com/forums/997-gt2-...e-control.html

I have this setup with FVD center bypass-it's nice but I've been thinking of going the same route Rick is talking about, with the TPC side deletes which do have the valves-the day Rick posts a video we can get a good idea of what it's like

balefire

Can you control the bypass of both the side muffler and center muffler independently?
Any videos?
I would really like to do the same for weight purposes.
Thanks!

jackb911

On the street IMO you will be much happier with a center muffler delete. In Sport mode, a GT3 so equipped is plenty loud, in normal mode there is zero annoying drone and you will easily pass Georgia emissions.

Guest89

Yep!

OP, just buy Sharkwerks or GMG. I daily drove a 997 GT3 with a Sharkwerks bypass, and I have an Atlanta friend who drives a 997 GT3 with a GMG bypass.

Sharkwerks has better customer service, GMG sounds better; nevertheless, both exhausts are actually pretty tame, and I never had an issue daily driving mine around Buckhead.

chillindrdude

guess i'm a cheapskate
i might try the speedtech one just purely based on price. i figure, the are all the same in terms of design, for the center delete.

Dan@SharkWerks

There are a lot of small differences to these that make a big difference in sound. It may not look like much, but those bigger, "megaphone" enlarging pipes and tips will give the car a Nascar or boaty like sound IMO .

We use smaller tubing than most of the others intentionally as we believe it gives the best / most exotic tone with no drone.

I've driven plenty of the other bypasses and we've taken off several "other brands" like the cheaper Ebay clones because they sounded worse. They also droned at freeway speeds. Ours also lets you re-use the stock exhaust tips, or change to our slashcut 88mm tips if desired - this may be a plus or minus to you, but it's a difference.

I would not recommend side muffler deletes for sound. They do take weight off the car but they sound much worse than a center bypass, again IMO. Ask someone who's heard and lived with both and I can't imagine how they'd prefer the side deletes for sound, anyway. To me it's like comparing the sound of a Ferrari V12 to a Viper V10 or maybe a modded UPS truck.