dnimi123

nice stuff!

electron mike

OK, I finally carved out some time to install the JCR rear section and go for a quick spin. First impressions (I have Akra OAP as well):

1. Cold start is an event, sounds rowdy!.
2. Above 4K is an epic RSR like flat 6 wail, love it!
3. The tone is a huge improvement over the completely stock exhaust as well as over stock rear with Akra OAP. Porsche - if you are listening, merge the two banks even if it robs a couple of HP and is a design pain. It's so worth it for the sound quality, even if it's not as loud as this more extreme setup.
4. Weight savings is significant! I might use the stock rear section for a boat anchor! The weight savings of the rear section and the OAP in titanium is very nice.
5. It does feel more powerful, but that could be because of the colder weather here. I'll find out how she does down the straights at the track to see if there are any measurable gains in power.
6. As others have said, there is definitely an increase in drone with the valves fixed open. It's annoying enough that I likely will not run the valves open all the time on the street. My plan is to plug the valves back in and see how it changes the sound at lower RPM and then possibly get a valve controller to keep them open for the track.
7. Fit and finish of the exhaust is excellent. On my car, it did require quite a bit of alignment and adjusting to get it installed. The clearance in several areas around the heat shielding and between pipes is very close, so I may have to adjust again and/or clearance the heat shielding if needed.

I'll try to get it on video on the street and at the track, but the videos I have watched don't quite capture the sound.. especially at high RPM under load.

TTFLT6

Nice! Good call with the megaphone tips, especially if they turn blue. I thought Jonny said this exhaust doesn’t drone

808c2s

I get the feeling that even the stock exhaust drone if it weren't for the valve closing below 4K. Switch it out for an aftermarket exhaust and OAP and it will be amplified if valves are kept open below 4K. That's my suspicion anyway.

TTFLT6

you're probably right, and we all perceive drone differently. Either way, I’m going for a better tone like the JCR.

DFW01TT

Thanks for recognizing the need for a "high rpm under load" soundtrack!
Stationary revving and doppler effect drive byes mean nothing to me in terms of real world sound.

Edge Addicts have a COTA event March 27 & 28, drop me a PM if you register.

Westcoast

Great that you have it and first impressions are positive! As you know, I have the valve controller, it works well to tame things down for the street, IMHO an integral part for these systems!

As for your comments in #7 above, I too had to fiddle about to get it all installed, my first go at the JCR section was with the OEM OAP'S I found it best leave all of the clamps on the JCR system loose until I messaged everything into position. Using this method all clearances were good with nothing close at all to heat shields, after the system went through a couple of heat cycles I went around and snugged up any clamp the was loose.

When I received my Akrapovic link pipes I took out the JCR system keeping all pipe-pipe clamps tight, when it all went back in no readjustment was need, everything was in the right place!

JCR-Porsche

Great feedback, thanks!

In terms of drone, the resonator pipes have some effect whilst the valves open but them and the silencers only really come into full effect with the valves operating as they should, having a valve controller on there tends to offer best of both worlds however on track the valves are pretty much open 100% of the time regardless anyway

In terms of fitting, the rear is made up of 5 different pieces and whilst we do align on the jig as the final QA prior to packaging the parts are only loosely clamped together and so it's likely that they will move a touch during transportation.

The sound of our systems never really truly come across on video, I think that can be said for all exhausts however the pitchy tone that we strive for is particularly difficult to accurately capture on film

Look forward to further impressions as you drive the car more and more

JC

electron mike

After running several different combinations on my car I agree. Some kind of silencing and resonator combination is needed on this car below 4K on the street.

I am trying to get out to COTA one day that weekend to make some noise.

I am beginning to see your wisdom! Pretty sure I'll get the valve controller as well. I'm hoping with the valves operating the drone will be livable on the street. I installed the same way with everything loose at first and its still a tight fit after adjusting. No rattling yet, I hope it stays that way.

Thanks again Jonny for making a great sounding exhaust system. The tone is really world's better in my opinion compared to stock and completely transforms the fun factor of the car!

TTFLT6

e-mike, What do the videos miss with the JCR sound? Is it deeper or higher pitched than the videos? Curious how you would describe the real world sound. Thanks!

Westcoast

@TTFLT6 I have had the same setup as above installed since last December, a decent number of drives experimenting with valve positions and in the Spyder top-up versus top-down... and will say that is tough to capture the sound in a way that when played back on your computer ithat it is fully there.

I have had enough time with the system to appreciate its sound and can pick this out in a video, but the video still falls short of conveying the complete experience. Generally the video will lack the fullness and clarity of the exhaust and each video depending on mic placement will be different, so pick a video and we'll tell you how close it is to the original!

Also remember that with or without the OEM OAP makes a huge difference as does valve control.

UncleDude

I have pretty much watched all the exhaust videos for every brand. The tone that got me thinking / wanting (note, I don't even have a car yet LOL) was the JCR rear section on the car guy video. While these videos don't capture the three dimensional sound of an in person experience, they are consistent in that aspect, including stock. So if none of them sound truly accurate, at least they have that in common!

What's your opinion on this one?

TTFLT6

Thank you, good info. I'm starting to think it's better to start with the exhaust/silencer vs. OAP, and then adjust w/OAP or gouge out the OEM pipe materials if you want more volume. We now know the OAP's don't add any meaningful HP gain.

Westcoast

Regarding you starting point, that is where my journey began, the JCR Valved Silenced Race Pipe with stock OAP. My take on that combination, nearly perfect and I dare say more perfect then it is now with the Akra link-pipe, it had the beautiful x-pipe sound, clearly a performance flat-6 exhaust note and virtually no drone. So you might ask what was it lacking(?), maybe just a bit bit more volume, intensity and lower frequencies, IMHO the GPF matrix in the OEM pipes are very effective as a silencer.

Since we all have different tastes I agree that a great starting point would be the exhaust/silencer as it changes the sound through design and can include mixing as in the case of the JCR system, where as the GPF delete mainly only makes it louder, and that maybe too much for some.

Westcoast

I have auditioned that clip a few times and again just now, I think it can be considered as representative of the changes in sound that you would experience by adding just the JCR rear section, I think what is important to take from this is the change in the characteristic of the sound more than anything else. Sonic memory is at play here for me, when I listen to these clips I remember what mine sounds like and realize that the video is falling short of the real world sound. I can hear both the JCR sound and OEM sound in each sound bite and they do come out close but compressed.

I would say that this clip gives a very good indication of what to expect but understand that in reality the JCR system it has more impact then comes across here, the other thing I do like is how Damian presented this was to throttle the engine in a very similar way, given' her the beans the same way, I have watched video from the other manufacturers and don't recall they tried to keep this the same.

Another thing I might mention is it depends on what you as the owner is looking for, you may or may not want such a boisterous exhaust note and prefer to maintain a more stealthy sound, everybody is slightly different. I have had a number of NA flat-6 engine cars so I knew what I thought that I should be hearing from this 4.0l 400+ HP engine and it just wasn't there, IMHO the exhaust sound was being muddied up by the OEM system, the JCR Valved Silenced Race pipe answered the call for a clean more characteristic flat-6 exhaust sound.