IL_Pete

Thanks, everyone! Glad you are enjoying the reviews.


So the Kline OAPs can only be used with the Kline Exhaust, they can't be interchanged with other brands, it is a proprietary design. Otherwise I would be all over that! Thus the idea for the JCR plus the Cargraphics OAP with the Canister design. They offer that empty, or with a High Flow Filter. But I don't know if I have the energy to try another combination, I will run with this one for a bit and decide what to do from here.

I watched Kit's review again tonight. You are right, he mentions a resonance at 5,000 RPMs that he likes! (Twice.) I had watched that video a couple of times before, but hadn't remembered that reference, or connected back to that when I experienced it my car. I am sure it sounds great in a Spyder in CA with the top down, and it was fine with the windows down in a Cayman, but I didn't love it windows up. It wasn't horrible, just noticeable in a way I didn't love.

That has been great fun! We'll get together again soon so you can check out the Kline system.

I totally agree with your comment "You can listen to all the best recordings people do, it never equates the actual feel and experience you have by actually driving it." The videos can help give an impression of what it sounds like, but it is nothing like experiencing it in person.

I was thinking about the JCR in your GT4 - I bet it would sound pretty great. With the GT4 having less sound deadening and feeling more raw inside the cabin, I would bet the JCR's killer tone would match well with that. (Hmm, maybe I need my own GT4?)

SpydrGuy

Great post Pete. Can you compare the 2 systems with valves open with a controller versus OEM control? Did you get drone with either system with valves locked open?

Alpha Ice

I'm very intrigued to see what the Cargraphic high flow OAP's would do with the JCR rear exhaust. I don't know if I'll be able to make it away from the manifolds and rear section to even try removing the stock OAP.

GT4_trip

Wanted to post my experience with this set up in case it helps anyone. I ran the car with cargraphic valve controlled and JCR silenced exhaust for a while. Give. The numerous reports of drone when adding link pipes to JCR exhaust, I was shying away from changing the OAPs. Out of curiosity and little bit of experimentation, I bit the bullet and installed the FLAT 6 motorsport OAP.

first of all, I am really impressed with the quality of the link pipes. Considering they are heat shielded, they seem to be the best value for money for link pipes currently on offer. Installation was a breeze comes with new hardware that is singifixantly easier to work with compared to the studs on the stock OAP.

back to sound, I was expecting a lot of drone (based on reports here) and too much volume. To my surprise, with the valves closed, the silenced part of the JCR rear section does a really nice job of cutting down on perceptible ( to me) drone at highway speeds in 6th gear. With valves open all the time, there is more drone in the 2-3.5K rev range than previously. But I think the stock valve programming will keep it in check. As for the volume, I would say it felt about 15-20% louder with the addition of the OAPs. But I think the real difference is in the clarity of the sound, and the rev range it’s active in.

pre loudly the JCR section got to song only after around 4.5K rpm. The OAPs made the sound more perceptible at lower RPMs. Also, the sounds of the rear section is more clear and direct across the rev range.

I find my findings interesting as I bought the JCR from @Electron Mike because he was having too many drone issues with the Arka OAPs. I think drone is dependent on personal sensitivity and where the valves sit. And the silenced rear section definitely help IMHO. Would suggest folks who are on the fence about combining similar set up to hear in person to make decision based on what you hear and feel.

998R

Great review IL_Pete!

Yes you should try the Cargraphic OAP, I have a JCR Valved Silenced exhaust and I’m waiting for someone to try this combo 😀

Cheers,
Harry.

IL_Pete

Okay, will do. Ordered!

I ordered the version with the High Flow filter like Larry Cable's, with the shielding added like he did. Awaiting ETA.

This will be the final comparison. I am getting exhausted and my wallet is getting empty.

IL_Pete

Yes, sure!

The Kline system doesn't drone at all at ANY of the 3 settings of the PSE + VC, around 2,000 RPM. It doesn't even get a little bit of extra bass frequencies there that some might not call drone, and others would. It is the best combination of Exhaust plus OPF Delete OAP I have heard in that regard. I am a bit confused by that, as others on the Kline thread have said it Drones a little, but that it is not severe. Kit on YouTube posted a second video saying that increased bass frequency is there, but it wasn't bad. I have the SS Delete and he does not, and I have Inconel and he has stainless, one or both of those could be the difference. I would think a Cayman would exhibit that more than a Spyder, top up or down, though. But for me, ZERO drone and NO bassy resonance whatsoever in that RPM range.

I attribute the zero drone thing to the Kline's unique design. They flipped everything around, and have a unique canister design on the OAP.

However there is that resonance at 5,100 RPM that reduces and fades away at/above 5,700 RPM, that with windows up I find a little bit bothersome. For clarity, I have an injury to my left ear that is the primary issue here, from my Rock and Roll Band days. If not for that, it may not bother me, I might think it is exciting and cool like Kit commented on, others may agree. But it bothers that bad left ear for me. When I had the Soul OAPs with the VC and the stock PSE, that bothered my left ear as well, on spirited country road drives I drove with an Earplug in my left ear. I find that with the Kline, I need to wear an earplug in my left ear as well, to protect my ear from the resonance above 5,100 RPM. It is not as much affected when ripping through 1st to redline and 2nd near redline, more so when cruising in 3rd at/above that RPM level. It is manageable though, I just need to learn to drive around it. I drove for 3.5 hours and about 150 miles yesterday, and figured out how to easily do that. 5,100 RPM in third is 76 mph. It sounds glorious from 55 mph to 76 mph in 3rd (3,800 to 5,100 rpm). So if I go north of 76 mph (on my private airstrip), then I just shift to 4th. That is actually quite good, as it gives you excuses to shift to 4th and then back to 3rd. Shifting is of course great fun, and downshifting from 4th to 3rd in that 70 mph in Sport Mode with Rev Matching creates a FEROCIOUS sounding downshift that always brings a smile to your face! And also because it sounds so darn good from 55 to 76, it is pretty easy to keep it under 76 and have great fun, which is probably a good thing.

With regards to this notion of managing around the 5,100 RPM thing, I figured out that I was artificially NOT shifting to 4th in that RPM range because the JCR with stock OAP setup was too quiet in 4th and sounded great in 3rd. So really it was just a matter of relearning for optimizing for this exhaust, rather than artificially having to manage around that resonance at 5,100 RPM.

And one thing is for sure - it is A LOT easier to manage around something at 5,100 RPM than at 2,000 RPM. Driving in chill mode around town running errands, you can not avoid the 2,000 bassy resonance/drone. It can be very annoying - obviously everyone agrees as it is one of the most talked about topics on this forum.

Speaking of the ferocious downshifts above - with the Kline system comparing to the JCR with stock OAPs, it is really not a fair comparison. In my experience any time you delete the filter in the OAP, you are going to get higher volume and great tones at higher RPMs and higher throttle levels, more ferocious downshifts, and more burbles in Sport Mode in a GTS 4.0. (As previously noted, you get more Burbles in a GTS 4.0 in Sport Mode than you do in a GT4 - I conclude that the GT4's programming is like Sport Plus, optimized for performance.)

A more fair comparison between the two would be the JCR with an OPF delete OAP. The JCR was louder at full tilt with the Soul OAPs, and had all the burbles and ferocious downshifts like the Kline system. Because the JCR is less different in sound and tone between closed and open, with OPF delete it is probably a little more ferocious than the Kline, and more linearly progressive in the buildup of volume and tone, whereas the Kline is more Jeckyl and Hyde, is more so chill at lower RPMs or with Valves closed, and then explodes in volume and fun above 3,800 RPM. Both are fantastic.

However, the JCR + OPF delete had too much Drone for me in all 3 settings of PSE + VC. So that is why I can't compare, and why I want to compare with the CarGraphics OAP with the High Flow filter. That might be the right balance with the JCR of a bit more mojo and volume, without creating too much drone. We shall see.

The JCR with stock OAPs has just a little bit of drone in all 3 settings, least with PSE valves closed, and a little more with valves always open. But it is tolerable, it is bassy resonance that some might call drone and others may not.

The Kline is the king IMO of ZERO drone around 2,000 RPM, at least with the SS Delete and in Inconel. It has great capabilities for being in stealth mode, both with keeping the RPM down, and with closing the valves. Closing the valves keeps it pretty quiet until about 5,300-5,400 RPM, which cruising around town is super easy to stay under.

But still, there are things I prefer about the JCR as well, so I am looking forward to trying that with the CarGraphics OAP. After my long day of driving and testing yesterday, there is still no clear winner. I don't know which one I will keep. I will run with the Kline for a while, and then when my CG OAP comes in, try that with the JCR and decide. One thing is for sure - for me and my criteria and preferences, these are my two favorites!

Westcoast

I too run the Akra link pipes and the JCR Silenced Valved Race Pipe combination, if I want to go quietly then I set the CG controller to Auto and leave the PSE in the off position, but when I am in the mood I open the valves for the entire rev-range and let her rip.

For me the best of both worlds, Open give the intensity and sound 9ver a stock system, and in Auto it still sounds strong but not over bearing especially for a long drive.

TRZ06

I think another caveat is that you are referencing the GTS 4.0 and NOT the GT4. The cabin of the GTS and GT4 is quite a bit different. While you may have no drone, that may not be the case in the GT4.

IL_Pete

Yes, thanks for pointing that out! I completely agree, and have commented on that previously. I think the four different versions of the 4.0 will react very differently to exhaust mods, and particularly drone. Theoretically the GT4 would be most prone to drone, with the greatly reduced sound deadening versus the CGTS 4.0, and the hardtop versus the uninsulated top of the Spyder. The Boxster GTS 4.0 would I think be the least susceptible with the greater insulation between the engine and the cabin, and an insulated top and the ability to take the top down. The Spyder and the Cayman GTS 4.0 would be somewhere in between.

I drove @tdlondon 's GT4 again a few weeks ago, and was reminded of how much more sound comes through from the engine compartment. I have to say, I really liked it! It felt so raw and alive. It definitely makes for a much more exhilarating experience on a spirited country road drive. Along with that, came a decent amount of 2,000 RPM drone from the Fabspeed Exhaust and OPF Delete OAPs, even with the SS Delete. That said, it was GLORIOUS above 5,000 RPM!! It is not his DD, so that works great for him. Driving his car makes me think I should have a GT4 *and* and Boxster or Cayman GTS 4.0.

That is something often missed in our discussions here, which version we are talking about. When I read a post about an exhaust review and drone, the first thing I try to do is look at the signature and the avatar of the poster to see which of the 4 versions that person has, for additional context.

Kevin in Scottsdale

IL Pete, I'm curious to read your comment that you think the JCR is more raspy than the Kline. I've heard the JCR in person. At idle, the exhaust has a nice rumbly, poppy sound. However, once rpm's are added the sound becomes loud and clear. Kind of like a trumpet. I have not heard the Kline in person, but the videos available make is sound much raspier and throaty. Perhaps the stainless steel will have a deeper throatier sound that inconel does not have.

If I could have the 981 exhaust sound, that would be the best of all optionsl. Of all the exhaust combinations you've tried, which one comes the closest to the 981's raspy, throaty, character filled sound???

avgt4

I had JCR OAP + JCR Silenced exhaust on my car for about a month and it was the most glorious sound to me. The entire rev range sounded amazing and it was so hard not to drive like an idiot around town just to hear the sounds my car was making. Unfortunately I ended up having to swap back the OAP to stock as it was too much drone for me driving around the city. For me the drone from 2-3k was just too much for me and my ears were hurting after 30 minutes of city driving. On the highway it was actually quieter than stock while cruising.

If I had a spyder and 90% of my driving wasn't city driving I'm sure it would have stayed on. I have the silenced exhaust with stock OAP now and yes it still sounds amazing, but the tone is not as glorious as before. I did the sound symposer delete when I put the stock OAP back on, and for me the cabin is perfect now. The drone range is just from 1800-2000 but I go through that range so quick I can live with it. Even with just the exhaust on here its worth every cent to me. The stock exhaust tone was lackluster to say the least and putting on the JCR exhaust transforms the car so much.

If I had to do it again I would just get a non silenced rear JCR rear section because the difference with the valves opened and closed on this system is so small I cannot tell a difference. I am patiently waiting to hear about the Silenced JCR OAP they have under development to see if it will solve the issues.

mprog

I’m waiting for the JCR silenced OAP to match my JCR silenced valved race pipe. I should have one of the first shipped.

I love the sound of this car. I get compliments at track days (most recently even from a 997 GT3 owner who’s like “man that sounds incredible” and I of course had to reply “coming from the owner of THAT car it’s quite the compliment!”)

I am gonna do the symposer delete though…

will give my impressions when I get it set up.

IL_Pete

The good news today: CarGraphics had my Hi Flow Filter Shielded OAPs in stock! They will be shipping soon, to try that with the JCR Silenced Valved Exhaust for the next experiment in this ongoing exhaust journey.

The not as good news: My trusted installer is having some surgery tomorrow. He will be out of commission for 3 weeks or so.

Looks like I will be rolling with the Kline for a while, while I wait for my installer to be back in the saddle! No worries, the Kline system is great, and it will likely do me some good to get some more time with it to really get to know it. I have driven quite a bit since the last post here, will post some more thoughts here soon.

IL_Pete

Maybe we are thinking of the word raspy as two different things. I am thinking of it in a way that the JCR sounds when it lights up, there is a sound I hear that seems like a resonance of the titanium. I really like it! It sounds very "motorsport".

I don't know that I have heard the 981 exhaust in person, but from the videos I have seen, the Kline is definitely closer. Very similar. The JCR in contrast is more GT3-like, more Motorsport. 981/Kline more Hooligan sportscar like, the JCR more Racecar like, if that makes sense.

Yes, everything you describe here is consistent with my experience!

I am trying the High Flow Filter CG OAP to try something "in between". I will be very interested also to hear how the JCR Silenced OAP is when it is released.


Awesome, cool to hear you will be getting one when they come out!