DJN

Videos posted on-line always demo this system with the additional 100cell cats with stepped headers (indeed this is loud_........) putting this cat back system on OEM cats passes TUV sound testing....and therefore much quieter.

Note that the best way to minimize sound levels and drone is the stay with the OEM exhaust system.....everything else is a compromise. Happy Hunting!

JB911

I just bought a used set of TPC valved sides and will combine it with my FVD/M&M center delete. There are a lot of people using the Soul center delete with their valved side deletes, and I bet this setup is pretty loud especially during the cold start process. I plan on starting with the garage closed and maybe a wet towel over the tips late at night until the air pump kicks in to quiet it down a bit
But at this point I want loud, too many electric scooters and idiots around town, at least if I'm loud it will scare people and wake them up.
I already have 2 extremely loud Kawasakis anyway.
Saw 3 Apollo V12 cars yesterday at the Design district Concourse here. Didn't stick around to hear them fired up but from watching videos on youtube, those things are factory loud! Mustangs, Camaros, Hellcats, seems everyone is running straight pipes these days

Joe@Fabspeed

JB911-----I totally agree----- LOUD PIPES SAVES lives is still in fashion. I ran Loud Pipes saves lives on my motorcycle and 993RSR,
Here is the scoop on GT3 rear exhaust bits>>

The GT3 center muffler delete pipe requires dedicated engineering and Dyno development to maximize horsepower and achieve magical flat six GT3 sports car sound. In 2006, my wall street friend and I air freighted in the 1st GT3 to Fabspeed Motorsport USA. Our team designed, tested and dyno developed 4 different styles of rear Gt3 center muffler bypass pipes. Some lost -7HP from stock and others gained upwards of +7HP versus stock. Its all about the design, testing and engineering.

I can assure you that there are many versions of GT3 center muffler bypass pipes and of course all make the car louder. Some versions immediately reduce power by -7HP versus stock. The best versions have a top mounted cross-over balance tube and these offer superb sports car sound and maximum pitch. Any GT3 rear muffler bypass pipe system that consists of 2 quantity 90 degree bends with a horizontal balance tube ( that has the two left and right exhaust banks colliding in the middle) immediately reduces power as the exhaust pulses smash into each other. Some systems cost a GT3 a precious -9hp.

GT3 side muffler bypass pipes with and without valves are a Fabspeed speciality. Our team designed these way back in 2006 on the same car. Over the many years we have used Pierburg exhaust valves and later Chinese exhaust valves as that was all we could get at Fabspeed. 6 years ago Fabspeed was contact by Helical Limited Aeropsace U.K. . Helical is the OEM Tier 1 supplier to Porsche, Lamborghini, McLaren, Ferrari, Aston Martin and other serious sports car manufacturers. The Helical U.K. vacuum actuated exhaust valves NEVER EVER fail, rattle, melt or flutter like all other cheap valves do.

Fabspeed Motorsport only uses Helical valves that we import from England so our customers never have failures.

JB911

JB911

I ended up with a big issue using the TPC side deletes and my FVD/M&M center bypass. From what I've determined, the TPC pipe dimensions work mated to the oem center muffler, but not to center delete. It's about 1-2mm too wide to connect to the center bypass. I've searched and both Soul and Fabspeed seem to connect to Sharkwerks, GMG and their own center deletes, so I'll have to return the TPCs

I detailed it in this thread:

https://rennlist.com/forums/997-gt2-...e-deletes.html

JB

Mr. Adair

Thank you for the update. Sorry to hear. I was following your thread. Keep us posted..

JB911

Well, the Soul has been used with all the major center deletes like Sharkwerks and GMG, and my FVD is made in Germany and fits the oem sides perfectly so I suppose it will not be an issue. I measured oem side pipes again this morning and it's pretty much 63mm with a slight taper at the edge.
More recent encounters with electric mopeds and scooters, many drivers with NO lights on at night(why is this a frequent thing these days???)
It makes me want it loud to scare these zombies, so thats where I'm headed

JB911

I have to add that my experience is not meant to knock down TPC's product. They probably meant it for the OEM center muffler and the extra mm doesn't make a difference. I did not want to try finding a specialized exhaust shop to modify them to fit my center delete-

Thnx

John

JB911

After this whole ordeal I spoke to John at Soul and ordered a set- one thing I didn't know, the positioning of the valves on their side deletes differs between the 997 and 991 models. I think this isn't the case with all manufacturers

Should be receiving them by wednesday and they should be a perfect match.

JG 996T

So goal is to delete all mufflers and keep valves?

Curious - Why didn't you use FVD valved side deletes?

JB911

The FVD valved deletes have to be made to order, would have taken forever I think. A friend ordered a muffler for his 964 and it took quite some time. When I spoke to Rhonda when the valved deletes were introduced she said she didn't have them in stock, and I imagine these days theres really more demand for 991 exhausts, and from speaking to John at Soul the 991 and 997 have valves in different area-
Yes, goal is to have valved side deletes+center delete. There's a video of a 991 with this setup, sharkwerks if I remember, and with valves closed it sounded acceptable to me. I also have the Carnewal remote to open and close valves at will-

Best,
JB

JB911

Just finished installing tonight, I put details on the install thread I started. 1mm difference in diameter was the issue-

JB911

I've continued my valved side+center delete ordeal on the install thread-

I've had some ideas on bringing the sound level down a bit, and have been favoring valves closed for now. The vendors and manufacturers don't participate as mush on the 997 forums, so there seems to be more input on the 991 world. I might try the stainless steel perforated sheet idea I had. Guys with all sorts of exhaust configurations are having trouble at certain tracks that have strict dB levels. There have been some developments on muffled tips, but they end up expensive. In the motorcycle world there are lots of affordable "dB killer" inserts, and dynatech makes them for cars too but I didn't see a setup less than 3" in diameter. But maybe they'll make them custom order-
https://rennlist.com/forums/997-gt2-...l#post16454351

drl

bonehead -
curious your thoughts about this set up now that you have had a chance to drive it more. I have the same set up on my new (to me) 997.2 RS; I have the valved SOUL side delete but am running it without use of the valves, in combo with shark center. It is loud! On my last 997.2 RS I had sharwerks track pipe for a while, but that was mostly used on track. The current set up sounds great, but it is pretty exhausting after a couple or more hours of street driving. This morning, I did a 3 hour drive and used earplugs most of the time. This was actually great, could hear all the good exhaust sound without any drone and without the ears getting beat up after so many hours. Still, seems kind of pointless for street driving to make loud exhaust, then use earplugs. For reference, on my 991.1 RS I have JCR valved (also not using valves) race pipe which is also loud but more manageable for long drives. So, still thinking about the direction I will take with the 997. Maybe just put the sides back on + shark center and call it a day. As it is now, the sound is great, whether at idle, rolling at low RPM, or WOT, sounds amazing. But too much for me after a couple hours or more.

bonehead

drl
100%. I could have written the exact same thing. It's ridiculously loud. But as you alluded to, it's also equally due to the drone at certain RPM's in addition to the actual decibels. I started using earplugs as well with any drive longer than 30 minutes and now think to myself that it's stupid to have to wear these things to make an extended drive more tolerable. I have essentially straight pipes on my FGT and used earplugs for the first few hundred miles after I installed them. For whatever reason, the sound has come down to a perfect level. Perhaps the drone 'worked itself out' after several heat cycles and a few thousand miles of driving?? Either that, or I'm just going more deaf.

So, I've also been contemplating going back to just a center bypass. I don't even want my 7 year old son riding with me and risk damaging his hearing. I do like the sound, but it's definitely tiring on the ears. My guess is headers (Dundon?), stock sides, and a center bypass would be the sweet spot. But I want to keep the cats. More importantly, I don't want to invest that much into something that may be an expensive disappointment.

Eager to know what you decide to do.