I’m so glad you posted this video. I was pretty much sold on the JCR especially after they claimed a 60hp gain on one of the videos I watched this week. This is very interesting!
That's exactly why I shared my experience, there are so many hyped up videos out there about this setup, and no one is actually talking about the downside of this product. An honest review includes both positive and negative. No one did an independent dyno run like I did, no one talks about the drone at 2K RPM. I wish I had access to this info before I purchased, hence I made this video. Glad I could help you in making a more informed decision.
@@blendlinegarage42 thanks. What did you end up doing? I get my car next week and now I’m considering either staying stock or going with Fabspeed as I had a great experience with their products in the past.
@@AverageCarGuy I def think the stock exhaust is underrated. If you want to add a bit of volume down the rev range, you can try disconnecting the vaccum lines (plug them and secure them). That would keep you valves open at all times and adds volume to the lower rev range. If you still needed some more volume, I'd go with kline or soul. Fabspeed is also good but the other two are a bit higher pitched. The Fabspeed makes the car sound deeper and more like an american muscle.. which comes down to your preference.
@@blendlinegarage42 went with soul full set up, it really woke up my car. The thing is you can’t tell unless went to the dyno. My honest guess n feel it made like 12 easily from early rpms - 30hp max or little more. This is a full exhaust, overaxless n catless headers
@@PS3Cooooooool yeah the full setup is absolutely adding that many HPs. My guess is majority of that gain comes from the OAP and headers. I believe the mufflers do little to generate back pressure as majority of the pack pressure is generated by the header & OPF filter. Would love to hear the car, please post a video.
Just saw your video, nice effort. From my drag knowledge; you make sure to match the same condition with lunch control so: - tank fuel level (yes it makes a difference even comparing quarter/half/full and same fuel - tyre pressures - your road pavement - filter condition - sway bars setting - did you drove around 600 miles after exhaust install for ecu to adapt? Keep your videos comying and nice pts you have, not jade green?
Thanks for posting this. Sadly I ordered a JCR system last week. But as my GT4 is just one of 7 other cars I have, I’m not too worried about droning. One point, your drag comparison isn’t quite fair, as the run with JCR I noticed the traction flash up, momentarily restricting power. Whereas stock run, it doesn’t. Eg looser surface, colder tyres etc… So not ‘apples to apples’ but thanks anyhow. Any other mods planned for yours?
I appreciate your comment. JCR is still one of the best sounding exhaust for GT4 and that's why I haven't sold mine just yet. As for the launch, I did several launches before and after JCR (you only see video for one). My best run (out of 6-7 runs) with factory exhaust was 3.9s. After installing JCR exhaust my best run was 4.2x (out of 6-7 runs). It is pretty normal for traction control to interject during launch control. There are many videos out there where people turn off traction control and get worse 0-60 times. I do agree with you in that it is not scientific and there is a lot of variables. That's why that is just one data point among other data points that help you as buyer to decide what exhaust to buy. Since this video I have installed OAP which was amazing. If you haven't seen the video, look it up under my videos.
Hi, great that you tested this and made a video. I have ordered the 718 Spyder (PDK, EU version with filter) and have also had the JCR on the plan. After your video I have become cautious. Sound agaainst HP is worst. At minimum Factory HP can be expected. Have tested your Car with more miles again ? The Drone is worst either. The Akrapovic would possibly be a good alternative. If you buy the Akrakpovic, do you do the same dyno tests again ? Factory with the then current miles and then with the Akrapovic ? Fuel standard: EU 98 is the same like US 93. The Fuel and Baseline was the same. Thank you. Cheers Rainer
Thank you.. yes you are right I was told EU 98 is same as US 93! I would say JCR sounds great but at best, you can expect no gains and at worst, you may lose a few. In a few months I will consider replacing the exhaust (likely with kline). If you look for sound, I suggest you look at kline exhaust. If you look for performance, I recommend Dundon. Akro is also great. If I buy another exhaust I will do exactly that, install OEM, do dyno remove, install and dyno again.
I don't have engine temp that shown in dynos but I know it was captured by Jotech. It should be similar bc in both scenarios I drove the car there, let it rest for 1 hour and did dyno runs. Ambient temps were similar, maybe a couple of degrees off.
I'm interested to see what your dyno results are now compared to a month ago. I wonder if it takes time for the ECU to adjust to the increased airflow of an exhaust system. I have the same JCR system, but sadly, I did not do any dyno runs to compare. I believe that Kline is the only other exhaust available that has the sound I'm looking for and it's even more money than the JCR. It's just unfortunate that we have to trade power for the sound we want. A couple other things I want to mention. I think you mentioned gas being "98" in Europe while you were using "93" - they use a different rating system there, you need to convert it to what we use to compare the octane level. It's possible that the Spyder you were referring to was using the same octane level as what you used. Drone - I noticed this as well at a very specific rev range like you described. I have a manual, so I don't encounter it much, but for anyone sensitive to drone, I would suggest they go with the silenced version of the JCR exhaust. I find it amazing that people continue on and replace the OAPs which introduces even more drone. I don't know how they tolerate it!
Great insights and thank you for sharing your thoughts. Yes OAP adds a lot of more drone and I have seen OAP + JCR setups that candidly loose the high pitch sound and are just loud
Love the spec on the car! I guess with the aftermarket exhaust being less restrictive and more free flowing you lost exhaust velocity. Basically the air coming out with less force, so it doesn't send the air out of the exhaust as fast as the OEM exhaust. Example a garden hose when you hold your finger against it and the spray becomes stronger. Anyway, have you found out yet why did the power decrease?
thank you! I know exactly what you mean. I added wider diameter exhaust tips to my base cayenne and noticed the exhaust would come out very slowly, almost like smoke raising when you make bone fire, lol! thats not the issue with this car, its a 4 litre engine and the flow is pretty strong. Not sure what happened with exhaust but even since this video I replaced the overaxle pipe and removed the particulate filter so the whole system post cats are straight piped now. Much better sound and performance. will do dyno soon and share the results here
you shouldn't be that surprised, the pipe length is the main factor here, thats why porsche explain the slightly lesser hp of the gt4 rs compared than the 992 gt3. Anyway this is an Xpipe, so is a longer route thn the oem. So probably you will gain hp just by doing the OAP OPF delete , keeping the oem backbox, and opening the valves from the beginning with a controller. You could be right about akrapovic , but you will pay a lot for the same oem result.
Cargraphic seems to be a very good exhaust as well. I think Cargraphic is a steel exhaust but I maybe wrong. I was focused on getting titanium for the higher pitch sound.
Not the first time I have seen a loss with swapping out the oem system. Really you only need to plug up the vacuum to actuator lines or wire the actuator closed, keeps the exhaust fully open all the time and the stock exhaust then sounds great. Or if you want to have fully open or oem with switchable control then the Soul controller.
Agree, that seems to be the only way to go.. I may just plug the lines as I always turn off the valves within the first 20 seconds of getting into the car.
@@blendlinegarage42 Plugging the vacuum lines might introduce more drone since the valves will be always open. But it's worth trying it out, I plan on doing the same next summer.
I think the back box replacement from JCR loses power because it keeps the restrictive particulate filter and then further restricts it with narrow (albeit straight through ) piping downstream. The stock back box served as a big negative pressure dump space to better draw out the flow through the particulate filter. You have to go all the way with the less restrictive headers upstream to provide enough impetus to remove sum total restriction all the way out of the tail pipes. So JRC's race back box replacement, despite what they tell you, is just for sound with some loss in power and torque. The full system (catless or with high flow replacement cats) is for even better sound AND more performance. Here in the states, my 718 spyder has equal length 621 SS ( better heat tolerance , better exhaust gas corrosion resistance) headers with the high flow 200 cell cats located all the way back at the axle. From there back, the particulate filter is deleted all together (single pipe to single pipe).and from there backwards there is a huge inconel 625 cross flow megaphone pipe exiting out of two 3 inch diameters tail pipes. That crack pipe not only receives unfiltered gas pulses (other than the performance cat restriction ) but carries alot of volume, has smooth cross flow characteristics, is complete straight through with no muffler at all and and has a more Porsche RSR aggressive sound tha JCR's. Yeah there is drone at the same rpm range as yours, minimal rasp, but does not sound restrictive and feels it when driving. Never Dynoed. That JCR back box replacement sounds restrictive though it is louder than stock.
Thanks for sharing this video, why? The reason you have lost power is you also need to tune the ECU. To keep it simple, the computer in the car is limited the new flow of air. If you can, upgrade the whole exhaust system, get a valve controller so you can truly control the exhaust system. Then get it tuned. After that you’ll see the gains easily. Without that tune forget about any increase in power.
You should not need a tune for a cat-back. There are no sensors after that point, and if it flows a bit better the gain should be in the fact that the engine uses less power to push the exhaust out.
It sounds like the exhaust system is set upbfor higher flow which it's having trouble doing with the stock headers and cats. Delete those and tune it. See what that yields for you
I have Akro OAP coming (which will delete GPF). Will do another dyno run then. I am hoping to get a touch more power without having to mess with the ECU (but that may not be possible)
@@blendlinegarage42 I've never heard of an ECU causing the power to be less. I have seen it were aftermarket exhausts have drastically different flow rates which will cause all sorts of small power losses or gains.
where did you get the gold sticker? i want to get a GTS sticker? sorry for your (power) loss, unacceptable considering this is a high end expensive system IMHO
Buy the way. I love the Green. What a great car and nicely spec' ed. But this should be a lesson to everyone. Porsche spends a shitload of money to get a performance AVERAGE It takes years and 9 figures to reach that average, BUT for some unknown reason I've seen too many cooks want to spoil the broth! And on top of that ... they haven't a clue. Manthey racing is the skunkworks for Porsche handling and product design .... but they don't mess with the powertrain. All the gains are made with suspension.Now you know why. I bet if you had race professionals install it and tune the ECU to the new setup they would get something MORE instead of less. And the one thing you NEVER want to do is void the warranty As a two time Porsche owner of new cars I speak from experience. Thank you for being honest! Most won't admit they made an 7K error in judgement.
they sure don't guarantee anything. There is a big thread on rennlist that I started with them and you can read their responses and judge for yourself. I was disappointed. rennlist.com/forums/718-gts-4-0-gt4-gt4rs-spyder-25th-anniversary/1271186-lost-10-hp-with-jcr-exhaust-non-silences-valved-race-pipes.html
Mate what’s the latest on this? I was considering buying JCR for my 992 GT3, I am based in the UK, I asked him for details of his factory, his quality assurance process etc. He went defensive and basically said if I ask him questions which he can’t answer then his product is not for me. I believe the guy just cooks up some Chinese made stuff somewhere with local welders and charges a premium for products which gradually impact your cars performance. With my GT4 in PDK from another UK based manufacturer I had a drop of around 20hp. Great sound but the day I put back the OEM exhaust back on, I could feel the car flying back again.
@@gurujojo8992 haha thats Jonny "Cocky" for you, mate. For 992 get R1 Motorsports. Check them out, better sound than JCR. Yes I also heard JCR doesnt make their exhaust inhouse, which explains the long turnaround time of 2-3 months (I can be wrong here though, I just heard this from another vendor)
also with my gt4, i noticed my 0-60 times slowed down by .3 seconds consistently after installing JCR exhaust. all his dynos and performance gains are in conjunction with oaps which do in fact make you gain hp. Backbox alone, best case scenario is break even, worst case scenario lose power like i did with JCR. Their gt4 system has resonators which can mess up the exhaust flow, i would feel more comfortable with just x pipes without valves as there is nothing to mess up with designing those
I will likely do another dyno in 2-3 months when it gets cooler with all the parameters in favor of getting more HP. If still underpowered, will likely replace it with either with Akropovic
@@blendlinegarage42 If you had a Silenced one I would swap it with you for my Akra! Seriously, the Akra IMHO is a glorified PSE. Bigger tubes, less muffler and 18 lbs less. But the sound is the same, just louder. I can't believe how long it had taken everyone to come out with a well designed muffler without having separates dual routes and most of them dumping the open valve route straight out each bank independently...it's a sound that' very un-Porsche.
They just basically came up with some excuses saying due to dynos being on different days (2 weeks apart) and that no fan was used to push air into intake, the results are invalid. Like I said in the video all parameters are similar with exception of humidity which was up by 15% but should not impact the results much. Both baseline and after dyno runs didn't use fans for air intake so the results should be consistent. I asked Jonny on Rennlist to provide additional proof of the added HP but he basically backed out. The only proof they have is the dyno run on spyder.
@@blendlinegarage42 Thanks for reply. Means, they didn't really care? Do u know the tolerance of that dyno? So far it sounds that the parameter and results are comparable, but not sure about the humidity can affect the results 🤔🤷♂️
There is a comment farther down that suggests that the Akra is just a glorified PSE. Based on the sound clips I've heard, I would agree. Only JCR and Kline seem to have a different, more desirable tone.
hp at wheel is different than hp at the crank.. there is usually 10% power loss through the transmission and diff. Companies report hp at crank not at wheel
Yes using PIWIS. I don't think the front wheels are supposed to move unless you are dyno testing an all wheel drive car like Nissan GTR. I don't think I have ever seen any GT4 on a dyno with front wheels in action
@@blendlinegarage42 Ok. there are some dynos that do move the front rollers to match the rear ones. But still it's a good idea to use a PIWIS to put it in rolling/dyno mode.
One thing I gotta say is the new model coming out with 500hp from the factory feels like a big slap in the face. This should have come with hp like that years ago. On one hand it's going to make older models cheaper. But 500hp and this sound = solid spring summer and fall daily.
Your dyno result says nothing about the so called lost horsepower after installing the jcr exhaust. Utterly nonsense because you test on another dyno than JCR. 10hp is probably the result of the flywheel setting on your dyno or more resistance in the dyna. Perhaps different altitude or a full fuel tank. 10 hp is not enough to make conclusions
UPDATE: I started a thread on Rennlist and engaged JCR. Here's the thread, judge for yourself: rennlist.com/forums/718-gts-4-0-gt4-gt4rs-spyder-25th-anniversary/1271186-lost-10-hp-with-jcr-exhaust-non-silences-valved-race-pipes.html
