BrntRubber

I just wanted to take a minute and comment on the amazing service JCR have provided.

Good, honest people highly skilled in their craft. I can’t wait to share the system on my car very soon!

Jangobipbip

Sounds good and high quality. Do you have DB levels?

JonathanWalker

Have you gone for the silenced or non?

BrntRubber

I am leaning towards silenced at the moment

JCR-Porsche

Thank you very much for the compliments

We will be sharing a ton of specific data next week once we complete the dyno testing including dB meter readings.

We will also be sharing results from a car on-track too so all relevant dB meter readings will be shared at that point.

JC

JCR-Porsche

The parts are now live on our site and available to order now

991 GT3 RS (OPF) / Speedster - EXHAUST PRODUCTS

JC

RSninja

I think you live around the block from me. Are you the guy with a carbon’d up grey RS? Please would it be possible to hear your car as I’m thinking of putting an exhaust on mine?

Thanks

pr0b3

Hi JC,

Do you have already some videos and performance counters?

Looking forward!

Cheers

JCR-Porsche

We’ve been on the dyno yesterday and will complete the testing today. Everything will be compiled over the weekend and released Monday..

In reality I’ll probably put some things out prior to that as it’s already been tough holding back the results!

JC

pr0b3

hmmmmm... I'm so curious

rshanholtz

JC - curious. Were you able to dyno both the EU Speedster with OPF as well as the WoW Speedster with the metal mesh in place of the OPFs? If yes, curious if the baseline dyno was different between the two systems before and after adding your "can't wait" system.

JCR-Porsche

Just the OPF cars at the moment, sound will be improved on the ‘mesh’ cars I expect.. we will see and it’ll be an interesting comparison for sure!

Great couple of days testing, went very well. I’ll be compiling the data video and images over the weekend and sharing Monday..

In the mean time a teaser video below


This is with the non silenced OPF Race Pipe installed.. It sounds absolutely glorious!

JC

JCR-Porsche

Hey all,

A day behind what we promised so I must apologise however we have got the footage together and created a video attached below showing our dyno test results from the 991.2 GT3 RS installed with factory OPF


Below we have gone into a little more detail about the testing. Worth noting that this dyno is a linked dyno and the car was placed into dyno mode using the factory Porsche tool to ensure consistent results. AIT's were monitored and all tests were performed within a 3 hour time window. The ambient temp crept up in the dyno cell during the testing which could well have lowered the results for the JCR exhaust figures but we're ok with that.

Baseline Figures

We were pretty surprised to see the baseline figures so strong after reading so much about the OPF cars being slower than the previous generation. I guess Porsche managed to claw more back with the ITB / plenum arrangement and quite possible that they're leaning on the motor a little harder too. Either way the figures are very solid with the measured 449.69whp & 317.60whp sitting as an estimated 530.63 crank HP & 374.76 crank TQ.



Of course the purpose of this test is not to focus on the headline figures, only to compare the deltas but using the recommended 18% driveline loss calculation recommended for this particular dyno when running in lined 4WD mode this is where we ended up.

• Weight Saving - N/A
• 449.69whp (530.63bhp)
• 317.60whp (374.76bhp)

JCR OPF Titanium (Silenced) Race Pipe

After the baseline testing we installed the JCR Titanium (Silenced) Race Pipe to compare vs OEM





Results

• -12.08kg (26.63lbs) Weight Reduction vs OEM
• 460.82whp (543.77bhp) // +11.13whp (+13.14bhp) vs OEM
• 323.03wtq (381.18tq) // +5.43wtq (+6.42tq) vs OEM

Key points

The results we're extremely encouraging, picking up torque in the low rpm was a little unexpected and gains were found throughout the full curve smoothening areas in the OEM curve which could be associated to valve switchover with the electronically controlled valves.

We also found that another added benefit is just how much less prone the car is to gaining temperature, the reduction of temps were very apparent vs OEM and as a result the consistency of the results were improved upon.


JCR OPF Titanium (Non-Silenced) Race Pipe

The final configuration was our non silenced version, offering maximum weight saving and added sound.




Results

• -13.86kg (30.55lbs) Weight Reduction vs OEM
• 461.62whp (544.71bhp) // +11.93whp (+14.01bhp) vs OEM
• 319.86wtq (377.43tq) // +2.26wtq (+2.70tq) vs OEM

Key points

Again similar results to that found with the silenced version of our Race Pipe with torque gain low down and eventually ending up a touch stronger at the top end all accompanied with that signature JCR sound. Again the consistency was improved over OEM with the heat build up and recovery much improved, in the real world this will be even more apparent.


Overall extremely happy with the results, not only a vast improvement in sound but excellent weight savings and proven gains in power and torque vs OEM

As ever, any and all questions are very much welcomed!

JC

EST

Very nice results Jonny !
Here is proof to the "speculators" that the OPF-ITB car has "less power and is slower"

Decibel information ?

Jangobipbip

Really nice job. If silenced version is not too loud for the Nordschleife I’ll certainly order one.
Waiting for db levels.