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JCR // DYNO TEST (Part1) - JCR vs OEM vs XXXXXX Headers

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JCR // DYNO TEST (Part1) - JCR vs OEM vs XXXXXX Headers

 
Old 02-01-2019, 12:51 PM
  #31  
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Just here to remember that when Dundon released their product, their main barrier was that a LOT of people didn't believed the gains at all, said it was impossible, blahblah, and now this.
Competition really is an amazing thing. Now just waiting for someone to improve and push the envelope even further.

P.S. Very glad to see exhaust manufacturers using proper materials for the class of the car, not that cheap **** 304 that apparently was bathed in gold given the prices. Really hope you guys expand and just put them out of business, preying on people ignorance is never a good business practice.
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Old 02-02-2019, 11:42 AM
  #32  
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Thiose are the highest stock torque numbers I’ve ever seen on a .1 RS. How was this dyno calibrated? The stock torque values look like a .1RS motor but the HP numbers look like a .2 GT3/RS.
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Old 02-08-2019, 12:41 AM
  #33  
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These headers look gorgeous. But the tube length looks shorter than the Xxxxxx and the bypasses are 70mm as opposed to 76mm for the competitors.

So the fact they they flow higher than the competitors but make slightly less torque early on doesnt make any sense.

I’m in the market for headers and these are priced reasonably, especially if someone already has side bypasses. Would love to see an independent dyno of the two to verify these results as from a physics standpoint on a NA car, shorter length primary’s and a smaller diam collector shouldnt make more power, they should make less.
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Old 02-08-2019, 04:06 AM
  #34  
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Originally Posted by trompazo View Post
These headers look gorgeous. But the tube length looks shorter than the Xxxxxx and the bypasses are 70mm as opposed to 76mm for the competitors.

So the fact they they flow higher than the competitors but make slightly less torque early on doesnt make any sense.

I’m in the market for headers and these are priced reasonably, especially if someone already has side bypasses. Would love to see an independent dyno of the two to verify these results as from a physics standpoint on a NA car, shorter length primary’s and a smaller diam collector shouldnt make more power, they should make less.
Thanks for the feedback.

Thankfully there is an awful lot more to an efficient exhaust manifold design than simply increasing length and diameter in order to seemingly ‘improve’ flow characteristics. As our design visually highlights.

Flow isn’t the be all and end all, yes it’s important to get the gasses out as quickly and efficiently as possible but this doesn’t mean bigger is better. In your assessment you’re assuming that bigger means more flow, remember we’re not talking about a straight pipe of constant cross section, in which case you might be able to apply some basic Poiseuille logic.

In any case, thanks for raising this point to allow me to expand (no pun intended) a little more.

JC
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Old 02-08-2019, 07:18 AM
  #35  
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Surprised XXXXXX didn't make 950hp on the dyno with the fanboys on here.
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Old 02-08-2019, 03:27 PM
  #36  
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Originally Posted by rosenbergendo View Post
Surprised XXXXXX didn't make 950hp on the dyno with the fanboys on here.
I have never bought an XXXXXX product, but I will buy the headers that give the best overall gains. I have gone through many different headers on many different cars, and have had two sets custom built for one customs application. If you design the header well the match the RPM of the engine, there is still almost always a trade-off between Torque and Hp. Bigger is not always better as they can sacrifice torque.

I already have TPC Side deletes so the JCR headers would cost less than the Dundon setup as they won't work with other side deletes, so these are a good deal and appear to be lighter and very good quality.

But I am trying to wrap my head around how headers that appear shorter and have smaller diam collectors produce not only more torque (which is logical) but also more peak HP. This is not the Norm so I am trying to figure out how that happens.
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Old 02-08-2019, 06:10 PM
  #37  
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My Akrapovic headers don't look that much different than the stock ones, yet my 2016 RS trapped 0.2 secs faster consistently to 100mph in the VBox. Akrapovic claims a 22hp increase, and I believe it, and they have cats (100-cell) catless would put even more HP out.

Last week I tested the stock headers and JCR race pipes in my 2019 RS, same closed service road where I test my other cars. I was curious as I noticed a power loss switching from Akrapovic headers and JCR Silenced Race Pipes to stock headers and same JCR pipes. No data from the Akrapovic headers + JCR (car was still being broken in), but the new data and all 5 passes performed better than all the 40+ passes over almost 2 years at the same place with the .1 RS on multiple exhaust configurations. The .2 GT3 RS engine is showing its strength, and it doesn't longer feel underpowered compared to my .1 GT3 RS (that was the immediate feeling of .1 on Akra+side delete+center stock compared to a delivery miles .2 on full stock muffler and 13 miles on the odometer).

I'm awaiting what comes from JCR on the valved silenced race pipes. As loud as the JCR race pipes in loud mode, quieter than my silenced race pipes on closed-valves mode, and I'm awaiting dyno tests from the JCR headers with stock exhaust and other JCR parts to switch to these Inconel units.
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Old 02-24-2019, 04:01 PM
  #38  
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Hi JC,
Just wondering when you are likely to release this product ?
Thanks,
Mark
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Old 02-25-2019, 10:08 AM
  #39  
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Originally Posted by mt2000 View Post
Hi JC,
Just wondering when you are likely to release this product ?
Thanks,
Mark
Mark,

The JCR Inconel Race Manifolds are available now, ill be posting the full release on RL this week all being well

JC
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Old 02-25-2019, 01:09 PM
  #40  
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Old 03-02-2019, 03:06 AM
  #41  
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Originally Posted by JCR-Porsche View Post
Mark,

The JCR Inconel Race Manifolds are available now, ill be posting the full release on RL this week all being well

JC
will this work with the your titanium race pipe. Any sound clips of these headers with the race pipe?
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Old 03-02-2019, 07:46 AM
  #42  
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Cost and availability of these headers?
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Old 03-07-2019, 12:36 PM
  #43  
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Originally Posted by Lethalsleeper View Post
will this work with the your titanium race pipe. Any sound clips of these headers with the race pipe?
Yes, the JCR Inconel Race Manifolds are a direct replacement piece in place of the OEM manifolds / headers.

A couple of videos below of this combination, its pretty extreme! Not for the faint of heart...



Originally Posted by usctrojanGT3 View Post
Cost and availability of these headers?
The cost of the manifolds is £4995.00 GBP and they're available now, full release thread coming soon.

https://www.jcr-developments.com/porsche/product/991-gt3-rs---inconel-race-manifolds]ORDER NOW - JCR INCONEL RACE MANIFOLDS

​​​​​​​[/url]JC
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Old 03-08-2019, 12:37 AM
  #44  
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Geez and I thought seeing glowing steel front rotors on racecars was impressive!
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Old 03-08-2019, 08:58 AM
  #45  
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Originally Posted by JCR-Porsche View Post
Yes, the JCR Inconel Race Manifolds are a direct replacement piece in place of the OEM manifolds / headers.

A couple of videos below of this combination, its pretty extreme! Not for the faint of heart...

https://www.instagram.com/p/BtBzKa_l...on_share_sheet

https://www.instagram.com/p/BtO5NETl...on_share_sheet



The cost of the manifolds is £4995.00 GBP and they're available now, full release thread coming soon.

https://www.jcr-developments.com/porsche/product/991-gt3-rs---inconel-race-manifolds]ORDER NOW - JCR INCONEL RACE MANIFOLDS

​​​​​​​JC
That is running LEANNN AF. I don't know what will give up first a piston or the titanium pipe. Why not make it inconel like the headers?
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