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Yeah, that’s what I did the first session. Just got out of the pack. You’d assume in Open group people would know better… they should know better!
My second session was scrapped due to oil clean up.
and after that I just got out there at the front of the pack. That solved my issues nicely
I’m not sure about next steps… their mid pipe looks nice. And the headers make serious power. TBD
Whatever you do next you have to be careful...you already have a rear section that's basically no muffler......so the only two things keeping the sound reasonable are the GPF and the Cats in the OEM manifolds.
IMO if you keep that rear section you will be able to remove one of those two but not both.....maybe catted headers or an OAP with some kind of resonator or aftermarket cat.
Might be a controversial statement but I think all you need is an OPF delete (pick your flavor) plus a valve controller....car sounds great!
don’t see the need to make the car ear bleeding loud....but what do I know
Originally Posted by Bob Z.
For the most part you are correct - I am adding Soul Sport Headers w/high flow cats for some added power and deepness but just OPF deletes will work for 99% of those that want extra sound. I have an extra set if someone is interested - PM me for details.
The difference is with only the OAP GPF delete and no x-pipe in the rear section you still do not have the merged exhaust sound, that of a flat-6 but 2 pipes each playing back a 3 cylinder sound track...
I didn't necessarily want just more sound but a completely different sound, a flat-6 song from the latest 4.0l engine in these cars. If I find the volume too much I will put the OEM GPF pipes back on and keep just the JCR rear section, because yes it sounds that good!
Yeah, that’s what I did the first session. Just got out of the pack. You’d assume in Open group people would know better… they should know better!
My second session was scrapped due to oil clean up.
and after that I just got out there at the front of the pack. That solved my issues nicely
I’m not sure about next steps… their mid pipe looks nice. And the headers make serious power. TBD
Originally Posted by jmartpr
Whatever you do next you have to be careful...you already have a rear section that's basically no muffler......so the only two things keeping the sound reasonable are the GPF and the Cats in the OEM manifolds.
IMO if you keep that rear section you will be able to remove one of those two but not both.....maybe catted headers or an OAP with some kind of resonator or aftermarket cat.
mprog, I have the same JCR rear section and agree with jmartpr that the next exhaust pieces to be removed will drastically increase the volume and intensity of everything! Running just the JCR rear and the sound was awesome, adding the Akra GPF deletes made it a lot louder and it could be too much for some people, I like it and it works well in the Spyder but the cabin of a GT4 will amplify certain aspects of the sound. In my case for a 'mostly' street car I would not want it any louder than it is now.
Thanks guys, that’s my hesitation too. I’m not sure I want it significantly louder but will spend some time living with it before figuring out what to do next.
mprog, I have the same JCR rear section and agree with jmartpr that the next exhaust pieces to be removed will drastically increase the volume and intensity of everything! Running just the JCR rear and the sound was awesome, adding the Akra GPF deletes made it a lot louder and it could be too much for some people, I like it and it works well in the Spyder but the cabin of a GT4 will amplify certain aspects of the sound. In my case for a 'mostly' street car I would not want it any louder than it is now.
Probably the best would be a set of Sport/Catted headers.......better flow and power but still something in there to control sound level.
Probably the best would be a set of Sport/Catted headers.......better flow and power but still something in there to control sound level.
From a power standpoint for sure, for me and considering warranty I wanted to keep everything before the axel factory to eliminate or minimize any warranty considerations...
Probably the best would be a set of Sport/Catted headers.......better flow and power but still something in there to control sound level.
Cargraphic Headers and 200 cell cats with my JCR non silenced exhaust would be perfect. And yes the JCR sounds fantastic while being manageable in the street.
The difference is with only the OAP GPF delete and no x-pipe in the rear section you still do not have the merged exhaust sound, that of a flat-6 but 2 pipes each playing back a 3 cylinder sound track...
I didn't necessarily want just more sound but a completely different sound, a flat-6 song from the latest 4.0l engine in these cars. If I find the volume too much I will put the OEM GPF pipes back on and keep just the JCR rear section, because yes it sounds that good!
Nothing can make this 4.0 spund like the gt3 engine. It has different harmonics altogether. Merging the exhaust banks only can do so much. Plus it only revs to 8
In fact, both x pipes i heard in person didnt sound like a flat 6. The kline sounds like a ferrari v8 and the bc fabs sounds like a lambo v12 (with the headers). Imho
this engine is goofy
Last edited by Rennolazine; 04-12-2021 at 02:45 PM.
In fact, both x pipes i heard in person didnt sound like a flat 6. The kline sounds like a ferrari v8 and the bc fabs sounds like a lambo v12 (with the headers). Imho
this engine is goofy
Not that I have heard these configurations on the 718...
Originally Posted by Rennolazine
Nothing can make this 4.0 spund like the gt3 engine. It has different harmonics altogether. Merging the exhaust banks only can do so much. Plus it only revs to 8
For the record, I am not looking to make it sound like a GT3 engine, but surprised that a Porsche flat-6 with the same bore/stroke and firing order could sound 'that' different anyway... My only goal was to let the 718 4.0l engine sing 'its' song without constraints, and I am very happy how it sounds!
Not that I have heard these configurations on the 718...
For the record, I am not looking to make it sound like a GT3 engine, but surprised that a Porsche flat-6 with the same bore/stroke and firing order could sound 'that' different anyway... My only goal was to let the 718 4.0l engine sing 'its' song without constraints, and I am very happy how it sounds!
i completely agree. The engine harmonics are great the main thing is you cant hear the engine stock and thats so important for a car like the spyder. Even if you kick up the tone an octave or two, or just uncork the upstream components it has a unique character and it sounds porsche.... and not like a fart can. Porsche still engineered the stock muffler well and its not bad when it gets more flow in it. But stock the damn thing was like a hair dryer. Even with opf deletes it sounded hollow compared to the full decorked system. But i agree with the guy above things get real loud real fast with this motor when its deristricted.
In fact, both x pipes i heard in person didnt sound like a flat 6. The kline sounds like a ferrari v8 and the bc fabs sounds like a lambo v12 (with the headers). Imho
this engine is goofy
Have you heard a JCR exhaust in person? If not, I’d recommend it
JC
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I got my JCR Silenced Valved exhaust and installed it myself on Quick Jacks. Installation wasn’t bad at all. Removing the stock exhaust was very straightforward.
The JCR exhaust is gorgeous. Welds (to my layman eyes) look incredible. The whole assembly is a fraction of the weight of the stock exhaust. To make installation easier I loosened all the section clamps, which let me get it bolted to the OAP studs more easily (but still takes some elbow grease). To connect the factory vacuum lines you remove the metal clamp, and I confirmed with Jonny that you can just force the lines on the new valve connectors (nipples?) and they should stay on (I also used high temp zip ties to hold the lines in place on the diagonal support beams under the car, which will make sense to you when you’re under there). The support bracket then bolts to one of the factory support locations and you clamp the exhaust to it (also took some muscle, and it forces the whole assembly to align better and is held there pretty rigidly). Then make sure nothing is touching the heat shields (these are easily pushed out of the way to make more room if need be) and tighten down all the clamps again. After a good heat cycle, and things have cooled down completely, torque everything down again.
But yeah, the things screams! It’s f’ing awesome. There’s a very cool transition noise between throttle being applied and when you stop that’s really great and doesn’t come out in videos. In the high RPM’s it’s exactly the sound you want from a GT car.
Unfortunately my track day wasn’t great... 105dB brings out a lot of people, including a lot of drivers who think they’re racing and both don’t drive predictable lines nor do they let you pass. Additionally, I forgot my microphone assembly and so the microphones are just saturated with wind noise. I’m gonna try to get some recordings on the street when I can find some time.
Awesome exhaust ! I knew I wanted it from the first videos I saw of Jonny driving the JCR 718 GT4, and I’m super happy with it.
Glad you’re enjoying it! I’m sure it’s coloured up nicely now it’s had some track time
Have you heard a JCR exhaust in person? If not, I’d recommend it
JC
No but i will soon as my friend will be buying the rear pipe and i will post some clips and impressions. Looking forward to hearing it in person so you can stop asking me. Lol
04-12-2021, 12:28 PM
