nstymatt

Yeah I heard 997 and 991 GT3 exhaust stuff should be swappable..but 3k to guinea pig is a lot

flsupraguy

Do you have a website?

Soul Performance

The 997.1/997.2/991.1/991.2 side mufflers all have the same fitment, which is why our valved side muffler bypass pipes (valved and non-valved) are the same for every generation of GT3 save for the 996. That said, we have different part numbers for the different generations because we like to track how many we sell for each generation. It's interesting data, and all we have to do is change the part number to get it. I'd imagine a variety of manufacturers do the same thing, so I wouldn't read much into varying part numbers on exhaust manufacturer websites for the side muffler bypass pipes. The center muffler bypass pipes are a different story. the bumpers have changed slightly throughout the generations with smaller or larger bumper outlets requiring different tip diameters, and also distance between the center muffler and the bumper outlet requiring different tip lengths. You may find that exhaust manufacturers do actually have different center muffler bypass pipe fitment for different generations of GT3s, especially those that manufacture the bypass pipes with the tips welded into the system. Our tips are modular so we're able to use the same center bypass with different tip diameters and lengths to accommodate different fitment across the generations.

In regards to supporting the exhaust system when combining side and center muffler bypass pipes, this should be something considered in purchasing a setup. With few exception, when you delete a center or side muffler on the GT3s it relies on the other factory muffler supports to support the exhaust system. Deleting both center and side mufflers would essentially leave just the clamps to the headers supporting the exhaust, which will not do. This is why we developed our own custom support brackets to use with our combined center and side muffler bypass pipes (our Modular Competition Exhaust Package, soon to be added to our 997 GT3 website page). Here is a photo of the support brackets we developed.
We offer something similar to that Carnewal PSE Override, though it doesn't have the stored feature so that is pretty cool! Thanks for the reference, I'll keep that handy for some customers of mine that would like to tweak their exhaust in that way. Sorry to hear you can't make it this year, you've Really got to be on that registration, it sells out almost immediately. It is a superb group and we are happy to be working with Sean on sponsoring it this year. CF is a terrible thing, and everyone involved is excited to give back. It would be great to see you there next year : )

With a combined center and side muffler delete, most systems utilize a change in piping diameter to affect the sound level between valves open/closed. We've found that this makes a notable difference in sound level outside the car, though isn't as noticeable to the driver inside the car. That said, we have utilized an expansion chamber design in our center muffler bypass that does cut down on cabin presence at cruising speed more than simply having a straight pipe design. See our design pictured below as a reference.
The only CMB with top side mufflers that I've ever seen are manufactured by JCR out of Titanium. It is a pricey setup, but it does exist and is good quality.

As I mentioned above, the 997.1/997.2/991.1/991.2 side mufflers all have the same fitment, which is why our valved side muffler bypass pipes (valved and non-valved) are the same for every generation of GT3 save for the 996. The center muffler bypass pipes are a different story. the bumpers have changed slightly throughout the generations with smaller or larger bumper outlets requiring different tip diameters, and also distance between the center muffler and the bumper outlet requiring different tip lengths. I'd imagine JC should confirm fitment relatively quickly and do the tweaks necessary to the cetner bypass options to accommodate 997 fitment.

JB911

John Wartique's car sounds phenomenal-sure would like to know what exhaust it is:


At the beginning of the video there's a glimpse of the exhaust under the protection plate-

orthofrancis

Drones a bit under 4K RPM. OEM failed during city/highway driving after about a month. Plenty of others have reported center muffler blow outs with valved side deletes.

Current exhaust is Fabspeed valved side deletes and Dundon Quiet center muffler. It still is louder than stock, but I can make sound limits on track.



My wife hates riding in my car....

HarmonyJim

I think you just answered my question. I would love to lose all that weight of the side mufflers, but not at the cost of droning, and exploding center muffler units. Currently I have a SW center bypass. Looks like I will keep it heavy, quiet and non-self-destroying - and keep my wife loving the car to boot!! Thanks for the help.

bweSteve

^^^ I'm right there with ya Jim.

And I'm sure you saw over on the recent Carnewal discussion thread, I'm hoping that solution will give me the flexibility to enjoy "always open -or- always closed" valve actuation. I can't believe Porsche did not engineer that into these cars from day 1. That 3k / 4k close/open, based on vacuum, was a crappy idea.

It's the same crappy idea that the GM engineers did back between 1967 (for the RS Camaro hideaway headlights, which worked perfectly using electric),... and then messed it up the next year in 1968 when they converted that system to vacuum for the hideaway headlights. Errrg. My '68 hideaways are a PIA.

Oh, and Btw, I have QTEC QTP ELECTRIC cutout valves on the headers of my '68 too,... and that rattles windows in the next neighborhood over!! But the electric cutouts have worked perfectly for over a decade!!

=Steve