Notices
718 GTS 4.0/GT4/GT4RS/Spyder/25th Anniversary Discussions about the 718 version of the GT4RS, GTS 4.0, GT4, Spyder and 25th Anniversary Boxster
Sponsored By:
Sponsored By: Cobb

Comparison: Soul OAP+VC versus JCR Silenced Valved Exhaust w/ Stock OAPs

Thread Tools
 
Search this Thread
 
Old 09-26-2021, 04:36 PM
  #46  
Jon H
Racer
 
Jon H's Avatar
 
Join Date: Sep 2012
Location: Texas
Posts: 429
Received 227 Likes on 98 Posts
Default

IL_Pete - Thanks for all your reports / time / money spent on this subject.

I'm going with the "#2 option", using the BC Fabs Inconel Silenced Valved Exhaust, due to arrive in November.

I'll report back once installed.

The following 2 users liked this post by Jon H:
IL_Pete (09-27-2021), UncleDude (09-26-2021)
Old 09-27-2021, 04:54 PM
  #47  
kw23
Rennlist Member
 
kw23's Avatar
 
Join Date: Apr 2021
Location: VA
Posts: 25
Received 1 Like on 1 Post
Default

IL_Pete - great review, I have Soul OAP/VC on my gt4 and love it so far, a bit drone from 2500 to 3000 but glorious sound above 5000. Did you notice any valve rattle with PSE off and VC off? Mine rattles a bit and we suspect it's a leak in valve controller solenoid, haven't got time to lift the car yet but the vacuum pressue reads low at the valves
Old 09-27-2021, 06:27 PM
  #48  
IL_Pete
Rennlist Member
Thread Starter
 
IL_Pete's Avatar
 
Join Date: Mar 2021
Location: Autobahn Country Club
Posts: 812
Received 1,115 Likes on 430 Posts
Default

Originally Posted by kw23
IL_Pete - great review, I have Soul OAP/VC on my gt4 and love it so far, a bit drone from 2500 to 3000 but glorious sound above 5000. Did you notice any valve rattle with PSE off and VC off? Mine rattles a bit and we suspect it's a leak in valve controller solenoid, haven't got time to lift the car yet but the vacuum pressue reads low at the valves
Thanks!

I did not have any rattle with mine Soul OAPs.
Old 09-28-2021, 01:07 PM
  #49  
IL_Pete
Rennlist Member
Thread Starter
 
IL_Pete's Avatar
 
Join Date: Mar 2021
Location: Autobahn Country Club
Posts: 812
Received 1,115 Likes on 430 Posts
Default

Update here - @tdlondon and I did a comparison test of my new setup with the JCR Exhaust and stock OAPs (and VC and SS Delete), versus his GT4 with the Fabspeed Valved Exhaust plus Fabspeed OPF Delete OAPs, and a Valve Controller. (Also the SS Delete.)

First and foremost, it is important to note that there is a fairly significant fundamental difference between the GT4 and Cayman GTS 4.0 in that the GT4 has less sound deadening, and there is a lot more engine, exhaust and mechanical noise that come into the cabin. It makes the GT4 feel more raw, in a good way. The CGTS 4.0 still lets a lot of that noise in, it is just that the GT4 lets more in. Beyond just the engine induction noise and the exhaust noise, there is a lot of clickety clacking going on, you can hear more so the mechanical noises from shifts, etc. It is great in that regard with the GT4, but also might be a little more mentally fatiguing than the CGTS 4.0.

That is an important point I think when we all compare here, there are 4 718 4.0 models, and while all 4 have basically the same engine (minus 200 RPM on the GTS's) and the same exact exhaust setup, all four are going to be subtly different based upon the amount of sound deadening, and the roof construction.

Okay, so to the comparison. tdlondon thought that the JCR was about the perfect setup for a street car. It sounds terrific in all 3 of the valve settings, and really roars at WOT throttle and higher RPMs. But it is not TOO loud. Windows up, it is plenty loud and raw inside the cabin. Windows down, with the AWE wind diffusers helping to reduce the wind noise levels, I still find it a hair on the quiet side while cruising country roads. (We did that on our test - went on 20-30 minute drives on my country road routes with both cars, where you have the opportunity to wind out the RPMs.)

Then we took out the GT4. I immediately noticed the above with regards to the overall sensation of the less sound deadening letting a lot more of the mechanical sounds into the cabin - I really liked that! I had experienced his combination of the Fabspeed Valved Exhaust with the Fabspeed OPF Delete OAPs (and VC) a few months back, before the SS Delete. I could say with certainty that the SS Delete definitely did REDUCE the drone. It was still there, but it was definitely less severe after the SS Delete. Before, it was pretty unbearable to me, after it was more so an annoyance but bearable, especially considering the gloriousness of that setup over 4,000 RPMs! It really sounded fantastic at higher RPMs. Enough such that I was feeling jealous relative to the JCR exhaust only setup! It was similar to what I experienced with the JCR Exhaust plus the Soul OAPs, perhaps a bit more epic with the less sound deadening in a GT4.

My impression was that his GT4's drone (after the SS Delete) was a little bit less prominent than my drone for the 4 days I had the setup with the JCR Exhaust plus the Soul OAPs. Maybe not, we couldn't compare back to back, obviously.

Another thing that came out of the comparison was that tdlondon was impressed with the AWE wind diffusers, and I think he ordered a set already!

Lastly, it did have me thinking about a GT4 again, versus doing another CGTS 4.0. There are a lot of options that I really like and want that you get in a GTS 4.0, and I like the notion of being a little more under the radar with the GTS versus the much more bold race car look of the GT4, but still that raw feel of all the noise in the cabin was really appealing! I do now happen to have deposits on BOTH a CGTS 4.0 and a GT4, it will be interesting to see which comes up first and what I decide. (Maybe I should do both, and then decide which one to keep longer term? Ha-ha - I wish. I think my Bank Account says no.)

It was great fun, so nice to be able to do this comparison back to back with these two similar but different cars, with the two setups. Also great to share that with another fellow Porsche enthusiast!

The following 4 users liked this post by IL_Pete:
BrianShaw23 (09-28-2021), flynlo (09-28-2021), mprog (09-28-2021), tdlondon (10-14-2021)
Old 09-28-2021, 02:02 PM
  #50  
BrianShaw23
Advanced
 
BrianShaw23's Avatar
 
Join Date: Sep 2021
Location: Rancho Palos Verdes
Posts: 83
Received 37 Likes on 22 Posts
Default

Originally Posted by IL_Pete
Update here - @tdlondon and I did a comparison test of my new setup with the JCR Exhaust and stock OAPs (and VC and SS Delete), versus his GT4 with the Fabspeed Valved Exhaust plus Fabspeed OPF Delete OAPs, and a Valve Controller. (Also the SS Delete.)

First and foremost, it is important to note that there is a fairly significant fundamental difference between the GT4 and Cayman GTS 4.0 in that the GT4 has less sound deadening, and there is a lot more engine, exhaust and mechanical noise that come into the cabin. It makes the GT4 feel more raw, in a good way. The CGTS 4.0 still lets a lot of that noise in, it is just that the GT4 lets more in. Beyond just the engine induction noise and the exhaust noise, there is a lot of clickety clacking going on, you can hear more so the mechanical noises from shifts, etc. It is great in that regard with the GT4, but also might be a little more mentally fatiguing than the CGTS 4.0.

That is an important point I think when we all compare here, there are 4 718 4.0 models, and while all 4 have basically the same engine (minus 200 RPM on the GTS's) and the same exact exhaust setup, all four are going to be subtly different based upon the amount of sound deadening, and the roof construction.

Okay, so to the comparison. tdlondon thought that the JCR was about the perfect setup for a street car. It sounds terrific in all 3 of the valve settings, and really roars at WOT throttle and higher RPMs. But it is not TOO loud. Windows up, it is plenty loud and raw inside the cabin. Windows down, with the AWE wind diffusers helping to reduce the wind noise levels, I still find it a hair on the quiet side while cruising country roads. (We did that on our test - went on 20-30 minute drives on my country road routes with both cars, where you have the opportunity to wind out the RPMs.)

Then we took out the GT4. I immediately noticed the above with regards to the overall sensation of the less sound deadening letting a lot more of the mechanical sounds into the cabin - I really liked that! I had experienced his combination of the Fabspeed Valved Exhaust with the Fabspeed OPF Delete OAPs (and VC) a few months back, before the SS Delete. I could say with certainty that the SS Delete definitely did REDUCE the drone. It was still there, but it was definitely less severe after the SS Delete. Before, it was pretty unbearable to me, after it was more so an annoyance but bearable, especially considering the gloriousness of that setup over 4,000 RPMs! It really sounded fantastic at higher RPMs. Enough such that I was feeling jealous relative to the JCR exhaust only setup! It was similar to what I experienced with the JCR Exhaust plus the Soul OAPs, perhaps a bit more epic with the less sound deadening in a GT4.

My impression was that his GT4's drone (after the SS Delete) was a little bit less prominent than my drone for the 4 days I had the setup with the JCR Exhaust plus the Soul OAPs. Maybe not, we couldn't compare back to back, obviously.

Another thing that came out of the comparison was that tdlondon was impressed with the AWE wind diffusers, and I think he ordered a set already!

Lastly, it did have me thinking about a GT4 again, versus doing another CGTS 4.0. There are a lot of options that I really like and want that you get in a GTS 4.0, and I like the notion of being a little more under the radar with the GTS versus the much more bold race car look of the GT4, but still that raw feel of all the noise in the cabin was really appealing! I do now happen to have deposits on BOTH a CGTS 4.0 and a GT4, it will be interesting to see which comes up first and what I decide. (Maybe I should do both, and then decide which one to keep longer term? Ha-ha - I wish. I think my Bank Account says no.)

It was great fun, so nice to be able to do this comparison back to back with these two similar but different cars, with the two setups. Also great to share that with another fellow Porsche enthusiast!
I wonder if there is a way to remove some of the sound deadening in the GTS 4.0 models to make it sound a little more like the GT4? Has anyone done this?
The following users liked this post:
IL_Pete (09-28-2021)
Old 09-28-2021, 02:16 PM
  #51  
IL_Pete
Rennlist Member
Thread Starter
 
IL_Pete's Avatar
 
Join Date: Mar 2021
Location: Autobahn Country Club
Posts: 812
Received 1,115 Likes on 430 Posts
Default

Originally Posted by BrianShaw23
I wonder if there is a way to remove some of the sound deadening in the GTS 4.0 models to make it sound a little more like the GT4? Has anyone done this?
Brian - That is a VERY good question! As I wrote this up today, I was wondering the same thing.

That would be having my cake and eating it too.
The following users liked this post:
BrianShaw23 (09-28-2021)
Old 10-03-2021, 09:54 PM
  #52  
spyderphile
Three Wheelin'
 
spyderphile's Avatar
 
Join Date: Nov 2004
Location: Minnetonka, Minnesota
Posts: 1,360
Received 100 Likes on 80 Posts
Default

Let me echo everyone's compliments, Pete; this is an awesome, exhaustive review. Just finished reading the thread. You've covered every conceivable scenario and test variable! Thank you.

Recently, I had a chance to ride shotgun in forum member HoosierDaddy's GT4 (thanks again, Steve). He has the exact setup I'll be running, if I get this gen: Valves Permanently Opened + GPF-delete (Soul) + Sound Symposer-delete + Valved Exhaust (Soul). The drive lasted about 30 minutes. I recorded the entire session (phone in hand).

While driving, I could hear the sound being boomy right away. The boom is ever present while tooling around in town, in different gears. Minor drone is felt around 3k, in different gears. We had the windows down most of the time. In a Spyder/GTS, with top down, you're unlikely to feel the 3k drone. In WOT, it sounded bit coarse. To my ears, the overall sound characteristics felt different from traditional flat-six. No, I wouldn't call it motorsports-grade; my view, of course. Since then, I've listened to the recording multiple times. Hearing through the speakers located right next to me on the desk (KEF LS50 driven by Cambridge Integrated Amp), the boominess in the sound is well pronounced and the first thing you feel.

I listened to your recordings, with and without GPF-delete. They aren't boomy; just a bit on occasion, off-throttle. That is encouraging. Based on my very limited exposure, I would choose JCR with GPF-delete. I suspect Inconel version will refine the overall sound bit more.

Regarding GPF-delete with silencer, I fail to see the point. How is it gonna be different from N.A version of GPF (without soot-trapping coating)? GPF-delete with Silencer will kill the sound as much as N.A GPF. You might as well stay stock.

Would it be possible for you to record at 3k, in different gears, with windows up and steady throttle, please? We're not in WOT all the time. Steady throttle is where we spend most of the time. Here is another reason for you to go for a drive!

Thanks again.

p.s. If were to guess what you do for a living, I would say you're a software developer or an analyst; or, at least you once were as you moved up the ladder! It takes logical thinking to capture all the variables!
Old 10-05-2021, 11:51 AM
  #53  
IL_Pete
Rennlist Member
Thread Starter
 
IL_Pete's Avatar
 
Join Date: Mar 2021
Location: Autobahn Country Club
Posts: 812
Received 1,115 Likes on 430 Posts
Default

Originally Posted by the_rider
Let me echo everyone's compliments, Pete; this is an awesome, exhaustive review. Just finished reading the thread. You've covered every conceivable scenario and test variable! Thank you.

Recently, I had a chance to ride shotgun in forum member HoosierDaddy's GT4 (thanks again, Steve). He has the exact setup I'll be running, if I get this gen: Valves Permanently Opened + GPF-delete (Soul) + Sound Symposer-delete + Valved Exhaust (Soul). The drive lasted about 30 minutes. I recorded the entire session (phone in hand).

While driving, I could hear the sound being boomy right away. The boom is ever present while tooling around in town, in different gears. Minor drone is felt around 3k, in different gears. We had the windows down most of the time. In a Spyder/GTS, with top down, you're unlikely to feel the 3k drone. In WOT, it sounded bit coarse. To my ears, the overall sound characteristics felt different from traditional flat-six. No, I wouldn't call it motorsports-grade; my view, of course. Since then, I've listened to the recording multiple times. Hearing through the speakers located right next to me on the desk (KEF LS50 driven by Cambridge Integrated Amp), the boominess in the sound is well pronounced and the first thing you feel.

I listened to your recordings, with and without GPF-delete. They aren't boomy; just a bit on occasion, off-throttle. That is encouraging. Based on my very limited exposure, I would choose JCR with GPF-delete. I suspect Inconel version will refine the overall sound bit more.

Regarding GPF-delete with silencer, I fail to see the point. How is it gonna be different from N.A version of GPF (without soot-trapping coating)? GPF-delete with Silencer will kill the sound as much as N.A GPF. You might as well stay stock.

Would it be possible for you to record at 3k, in different gears, with windows up and steady throttle, please? We're not in WOT all the time. Steady throttle is where we spend most of the time. Here is another reason for you to go for a drive!

Thanks again.

p.s. If were to guess what you do for a living, I would say you're a software developer or an analyst; or, at least you once were as you moved up the ladder! It takes logical thinking to capture all the variables!
Sure, that is an assignment I will take, with regards to recording windows up. I will try doing a few different things in that.

With regards to "Steady throttle is where we spend most of the time" - speak for yourself! Even when I am cruising around town running errands, I tend to modulate the throttle to keep it interesting, speed up a little for that noise of slight acceleration, and then off the throttle for some burbles on the overruns. (54 years old, but still a child inside...)

EDIT: With regards to the guess on what I do for a living, not software, but I am in tech - run a team of salespeople and engineers selling Telecommunications Equipment. Good guess!

Last edited by IL_Pete; 10-05-2021 at 11:53 AM.
Old 10-05-2021, 01:01 PM
  #54  
Alpha Ice
Burning Brakes
 
Alpha Ice's Avatar
 
Join Date: May 2018
Location: Minnesota
Posts: 810
Received 460 Likes on 286 Posts
Default

Originally Posted by IL_Pete
Sure, that is an assignment I will take, with regards to recording windows up. I will try doing a few different things in that.

With regards to "Steady throttle is where we spend most of the time" - speak for yourself! Even when I am cruising around town running errands, I tend to modulate the throttle to keep it interesting, speed up a little for that noise of slight acceleration, and then off the throttle for some burbles on the overruns. (54 years old, but still a child inside...)

EDIT: With regards to the guess on what I do for a living, not software, but I am in tech - run a team of salespeople and engineers selling Telecommunications Equipment. Good guess!
We're only as young as we feel! There's a reason why Porsche owners look so good as we age
The following users liked this post:
IL_Pete (10-06-2021)
Old 10-07-2021, 12:41 AM
  #55  
spyderphile
Three Wheelin'
 
spyderphile's Avatar
 
Join Date: Nov 2004
Location: Minnetonka, Minnesota
Posts: 1,360
Received 100 Likes on 80 Posts
Default

Originally Posted by IL_Pete
..........

With regards to "Steady throttle is where we spend most of the time" - speak for yourself! Even when I am cruising around town running errands, I tend to modulate the throttle to keep it interesting, speed up a little for that noise of slight acceleration, and then off the throttle for some burbles on the overruns. (54 years old, but still a child inside...)
......
Fair enough! Actually, my driving pattern is likely similar to yours. Girl friend calls it "roller coaster ride"; and, called me a maniac a few times! And, she grew up with Porsches! Her brother is a big collector.

I meant, between the bursts of "exuberance", an interval of steady-throttle cruise as a means to calm myself down a bit!

Looking forward to your recording. Few minutes of steady-throttle cruise, with windows up, in 2.5k - 3k, in 4th, 5th and 6th would tell us about drone. Thanks.


Old 10-07-2021, 04:36 PM
  #56  
Tristan Chang
2nd Gear
 
Tristan Chang's Avatar
 
Join Date: Aug 2014
Posts: 2
Received 0 Likes on 0 Posts
Default

Pete,

Again, thanks for the wonderful review which enticed me to get JCR exhaust. Is there a dealership in US? Or have you directly purchased from UK? In that case, did you have to pay any tariff import to states? Thank.


2021 Boxster 25
Old 10-07-2021, 07:33 PM
  #57  
IL_Pete
Rennlist Member
Thread Starter
 
IL_Pete's Avatar
 
Join Date: Mar 2021
Location: Autobahn Country Club
Posts: 812
Received 1,115 Likes on 430 Posts
Default

Originally Posted by Tristan Chang
Pete,

Again, thanks for the wonderful review which enticed me to get JCR exhaust. Is there a dealership in US? Or have you directly purchased from UK? In that case, did you have to pay any tariff import to states? Thank.


2021 Boxster 25
Great, I am glad you found my review helpful!

I don't believe they sell through dealers, I purchased directly from JCR.

I am not sure with regards to a tariff. There may have been something built into the price I paid, sometimes also I get billed later by the shipment company for that sort of thing.
Old 10-08-2021, 10:34 AM
  #58  
Jon H
Racer
 
Jon H's Avatar
 
Join Date: Sep 2012
Location: Texas
Posts: 429
Received 227 Likes on 98 Posts
Default

I have an exhaust coming from the UK , the estimated tariff was around $350 on a $7K purchase.
But no VAT since it's coming to the US.
Old 10-08-2021, 11:42 AM
  #59  
Westcoast
RL Community Team
Rennlist Member
 
Westcoast's Avatar
 
Join Date: Dec 2019
Location: Victoria, BC, Canada
Posts: 9,192
Received 4,711 Likes on 2,741 Posts
Default

Originally Posted by IL_Pete
Great, I am glad you found my review helpful!

I don't believe they sell through dealers, I purchased directly from JCR.

I am not sure with regards to a tariff. There may have been something built into the price I paid, sometimes also I get billed later by the shipment company for that sort of thing.
I too purchased the JCR directly from JCR... they are very busy so expect a lead time.
Old 10-08-2021, 01:38 PM
  #60  
5Zigen
Intermediate
 
5Zigen's Avatar
 
Join Date: Feb 2021
Location: Vancouver, BC
Posts: 49
Received 44 Likes on 24 Posts
Default

I ordered directly from JCR as well, its been almost 3 months and waiting.
The following users liked this post:
Tristan Chang (10-10-2021)


Quick Reply: Comparison: Soul OAP+VC versus JCR Silenced Valved Exhaust w/ Stock OAPs



All times are GMT -3. The time now is 05:16 PM.