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loudest GT3 center bypass?

 
Old 01-03-2019, 04:04 PM
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NJRickD
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Default loudest GT3 center bypass?

do we have a consensus (or at least as close to one as possible for the internet) on what the loudest center bypass is for the GT3? I feel like my 997.2 with a fabspeed unit was louder than my 991.2 is with a fabspeed unit. I have valves unhooked but it always seems like I'm always okay with going a little louder.
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Old 01-03-2019, 04:14 PM
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sgroer
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I have tried many and the GMG was the loudest. We had them all lined up at smokies one year and it was noticeably louder. It's also the only one of the 6 or so that I've tried that got me black flagged for sound at my track.
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Old 01-03-2019, 04:19 PM
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the2thdr
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Originally Posted by sgroer View Post
I have tried many and the GMG was the loudest. We had them all lined up at smokies one year and it was noticeably louder. It's also the only one of the 6 or so that I've tried that got me black flagged for sound at my track.
do you remember exactly which ones were there? Aside from loudest, which one sounded best to you?
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Old 01-03-2019, 04:26 PM
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kyrocks
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CMS is as loud or louder than GMG. I have had both.
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Old 01-03-2019, 04:44 PM
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NJRickD
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I can't handle the tips on the CMS. So bad
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Old 01-03-2019, 05:00 PM
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kyrocks
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There is a new one. Classic round tips.
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Old 01-03-2019, 05:10 PM
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sgroer
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Originally Posted by the2thdr View Post


do you remember exactly which ones were there? Aside from loudest, which one sounded best to you?

I think RSS and their X-pipe design sounds the best, it has this unique exotic ripping sound that is unique and spine tingling... but the tips are not great. Sharkwerks is what I am going with on my 19 RS. It is up there with the best of them in sound - close to RSS and the fact that you can use OEM or aftermarket tips makes it pretty tough to beat.

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Old 01-03-2019, 05:45 PM
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Did not like the RSS X-pipe. Had it for 2 months and got rid of it. Felt like the engine was suffocating. Replaced it with a GRP and what a difference.

GMG and GRP the louder of the rear bypasses in my opinion
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Old 01-03-2019, 05:49 PM
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Originally Posted by Jimmy-D
Did not like the RSS X-pipe. Had it for 2 months and got rid of it. Felt like the engine was suffocating. Replaced it with a GRP and what a difference.

GMG and GRP the louder of the rear bypasses in my opinion
It's all subjective!
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Old 01-03-2019, 06:33 PM
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I've had GMG and SW. Prefer the tone on the SW better although it's not as loud as the GMG.
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Old 01-03-2019, 07:16 PM
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Originally Posted by kyrocks View Post
There is a new one. Classic round tips.
Here are a few photos of the new CMS GT3 / GT3RS exhaust along with the dyno sheet (more to follow as soon as product photos are finished). It scavenges even better than the old "infinity outlet" design which was, ahem, aesthetically controversial. Our goal is not just looks and sound (which you can get anywhere) but performance as well, which you can't get from anyone else. We're just ramping up production as it's a complex piece to make (we do everything in-house from design to fabrication to ceramic coating). But this gives you an idea of how it looks on the car. Slash cut like the OEM tips, sounds like a proper race car (which is to say awesome) designed for high-rpm scavenging.

We're offering Rennlisters a special New Years exhaust special: save $500 using code "2019EXHAUST" at checkout. You can buy one on our website here. This special ends on Jan. 20. Be sure to PM us if you have questions!






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Old 01-03-2019, 08:32 PM
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Originally Posted by CMS View Post
Here are a few photos of the new CMS GT3 / GT3RS exhaust along with the dyno sheet (more to follow as soon as product photos are finished). It scavenges even better than the old "infinity outlet" design which was, ahem, aesthetically controversial. Our goal is not just looks and sound (which you can get anywhere) but performance as well, which you can't get from anyone else. We're just ramping up production as it's a complex piece to make (we do everything in-house from design to fabrication to ceramic coating). But this gives you an idea of how it looks on the car. Slash cut like the OEM tips, sounds like a proper race car (which is to say awesome) designed for high-rpm scavenging.

We're offering Rennlisters a special New Years exhaust special: save $500 using code "2019EXHAUST" at checkout. You can buy one on our website here. This special ends on Jan. 20. Be sure to PM us if you have questions!





Wow, is that Dyno pre and post center only or other mods like a tune or side deletes? That's a crazy power gain for just the center bypass!
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Old 01-03-2019, 09:01 PM
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Never seen HP gains on a center bypass only.
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Old 01-03-2019, 09:16 PM
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Don't remove the center exhaust on an RS! It's a piece of art!
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Old 01-03-2019, 10:12 PM
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Originally Posted by ajw45 View Post
Wow, is that Dyno pre and post center only or other mods like a tune or side deletes? That's a crazy power gain for just the center bypass!
Yes, that is pre- and post-center delete only on an otherwise-stock 991.2 GT3. We learned with the original “infinity outlet” exhaust how much there is to gain from an outlet that functions as a scavenging device. It took a while to arrive at a design that has dual outlets but still creates the same scavenging. We were originally surprised by the gain of the original design, but this time around we were expecting it.

It it is unusual that a muffler delete alone does that, but the GT3’s center exit creates a perfect situation for this design. We were surprised that others simply resorted to the straight balance tube, which is not at all ideal in terms of high-RPM flow. It’s simply a device for tuning out drone.

The main drawback to our design is that it is very difficult and time consuming to make, so it’s taken us a while to perfect. But the result is more than worth it.
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