808c2s

True, true...else why would some one spend good money on something that sounds stock?

TTFLT6

You wouldn’t. My question. was for Jonny. He has offered decibel levels in the past.

808c2s

Fair statement. Looking forward to his input.

JCviggen

We're still in the early phases of modding the 4.0 platform I feel, but the data so far does not support the OAPs being major power robbers. The real world data we've seen from people with a financial interest in selling pipes has shown power gains from 0 to 5 or 6 HP. It also seems that some drone is hard to avoid when you ditch the (fake or real) OPF completely.

I agree that it's extra weight and a bit of an annoying thing to have on your car but the benefits of keeping it on are real I think. The comparison of stock headers vs. Aftermarket with 200 cpi may not be entirely relevant. Those cats are very close to the heads and interfering with exhaust scavenging. The OPF is very far back where it is less of an issue. If you want to run cats, getting a setup where the cats are in place of the OPF would be a great solution. Far superior to solutions where the cat is part of the header.

Personally I'm thinking to go race headers + performance rear section but leave the stock OAP in. I've heard what a "full" system sounds like and that's just ungodly loud. The stock PSE does an amazing job with valves closed but it will always sound like 3 plus 3 cylinders and the X-piped solutions all get loud pretty fast. So I see no other way than to keep the one thing that seems to do the most to keep the sound levels down.

Nish G.

I'm also in the market for a new rear section and having listened to sound clips from Fabspeed, JCR, Soul, Akrapovic, etc, nobody seems to come close to as good of a sound profile as JCR. Having said that, they and Akrapovic are also the most expensive, likely because they are titanium. It's difficult to justify $8000 CAD for just a rear section when sound improvement is all I'm looking for, not really weight savings. Since JCR has mentioned they aren't developing any other options for the 718 4.0L, I'm hoping another manufacturer is able to reproduce a similar sound signature with a more affordable stainless steel option.

Sausage416

the cargraphic race exhaust has a similar tone to jcr but it’s in ss.

Driven991

Recently contacted Soul performance and was actually told the opposite regarding the OAP. That is OEM OAP is restrictive and replacing it should result in about a 15 HP gain. Do any of these guys have dyno data for just replacing the OAP?

Nish G.

I must have been looking at the wrong Cargraphic models, because you're right, the X-pipe model does sound similar to the JCR. Not quite as good, but close. Thank you!

Cali

The SOUL kit is stainless steel as well, correct? I presumed so since it's same weight as OEM.

Nish G.

Correct. AFAIK, only JCR and Akrapovic offer titanium kits. Everyone else is SS.

Westcoast

The cost is relative to all aspects of the system, design and development, materials and difficulty to manufacture (hand made in limited quantities), include all 3 in the mix and the price goes up accordingly. Here in Canada we have the added bonus of a weak currency in most international transactions, and right now especially the British Pound which puts us at a disadvantage when considering the JCR products.

Don't get me wrong, this price point is not for everyone and the SS systems have their place and the advantage of lower cost however...

Personally I did not want a stainless steel system if I were moving away from the OEM parts, I figured that if I am changing out some of the exhaust system it will have to check the boxes in sound, lightweight construction and quality or for my I wouldn't bother. As you have probably figured by now I have the JCR Silenced Valved Race Pipe and Akra link-pipes and the sound is incredible, it is all Titanium and is a work of art...

Cali

This is the set-up I was eyeing, although I've heard rumblings that the Akra link pipes aren't available stateside anymore for some reason. Might have to wait it out for JCR's titanium OAPs to complete the set up. And save up the piggy bank money of course.

Westcoast

As these OAP's are part of a modular system the JCR units should be quite similar in nature yielding nearly identical results. It was all due to timing that I was able to get the Akra units when I did and don't understand why they are not generally available now, check with Eric at Supreme Power as he may know more.

TBH, the JCR OAP's were not available when I was ordering exhaust parts, normally I would match the system.

rahtid

The Soul valved rear section is SS but it does sound very close to JCR's exhaust. I'm having a warm time deciding which one to get. JCR is what the heart wants but wallet says SOUL lol.

From what I gather from this thread (thank you all for the feedback), my ideal setup might be the JCR valved non-silenced with OEM GPF and no valve controller. The valves still close automatically under 4k rpm? If that's the case that might dumb down the downshifting sounds and will need a valve controller. The only time drone will annoy me is on the highway.
Which gives a cleaner high pitch sound? the silenced or non-silenced valved race pipe?

JCR-Porsche

This is an example of our non silenced, it’s a touch crisper sounding due to no sound suppression or expansion in the rear section at all


JC