Soapman72

+1

I am curious about the headers myself. I asked about spool time a couple of posts back. Can you explain where (rpm) these headers are designed to operate most efficiently?

There is always a trade off in header design. If they designed them for more top end power, you will almost certainly give up some low end. I am tempted to say that it is not a big deal, considering the gobs of torque thew engines produce, but in a turbo charged engine, less exhaust gas velocity at low rpm can cause slow laggy response, which I want to avoid at all costs.

There is another manufacturer of 991.2 headers that admitted to me that SOME additional lag may be felt with their headers, and as mine is a street car first, this was a deal breaker

///M3THOD

Any update on the headers? Images, performance numbers, etc?

spdracerut

For NA cars, you do tune the headers to operate best in a specific RPM range by adjusting their length. With turbo setups, optimization of flow (bend radius, flow merge, etc) and equal length are more important and gains should be across the board. Stock manifolds are usually designed with cost a higher consideration than performance, hence there's often a lot of room for improvement with aftermarket headers.

This is from a 2015 WRX, upgraded vs stock turbo manifold:


This dyno plot is from an Evo X, Full-Race manifold vs. stock:

VektorPerformance

^ Exactly this. Pressurized manifolds follow different design and performance optimization rules compared to a naturally aspirated version. A properly executed turbocharged manifold design will improve efficiency throughout the rev range. If it improves only a portion of the rev range, the design was not optimized to its potential. Volume can play a roll in response, but often times a well executed header design will respond significantly better due to poor design factors or criteria from the factory log style manifold.

Soapman72

Not to be argumentative, but just because aftermarket headers can show an across the board improvement on a WRX, does not mean that the same improvement is possible on these cars. Not because I think Porsche engineers have developed better exhaust manifolds than the Subaru engineers have (although I do believe this is probably the case), but because there is no correlation between the possible gains on a completely different engine and exhaust design.

Another manufacturer has already admitted to me that their headers cause a slight loss of low end and a slight INCREASE in spool times, which is the opposite of what is like to achieve. I have no issue with putting headers on my car that focus all of their gains on the top end, as long as they will not INCREASE the small amount of lag that we all know is present in stock form on the GTS.

I'd love to hear from anyone here that has already tried these headers or the Fabspeed headers, so as to hear their impressions.

arter

Suggest you open your own thread rather than muddying up the Kline one.

Felix_Kline

Hello guys!
Sorry for the late reply to this thread, we have been extremely busy recently. Everybody wanting their systems before Xmas

The Kline headers gain in all rev regions. This is primarily achieved via the equal length design. This is particularly important on turbo headers, as the phasing of the gas directly affects the efficiency of turbo spool. The cylinders on the Kline design are exactly 120 degrees out of phase. This creates a faster spool, and more efficient flow in all rev regions The overall internal volume of the headers are the same as stock, so this does not increase spool time or create lag..

We don’t usually like to publish our Dyno graphs, partly because they are proprietary, but also because we propagate a “My Dog is blacker than yours” scenario. However, a dyno graph of the full system including headers is available on request.
Email anytime Felix@kline-innovation.com or Christian@kline-innovation.com

4 Point 0

I can't find pics of the Kline headers anywhere?

Valvefloat991

Stock headers are not only compromised by cost considerations, but they are also designed to minimize heat loss to promote catalyst warm-up time. Most of the emissions measured on the pollution tests are generated in the first 30 seconds, before the catalyst achieves its roughly 1000-degree operating temperature. Slicing even five seconds from this time produces a big improvement. It's easy to see how a simply log manifold has less surface area than a nice header with three distinct runners.

stout

^ Agree with your points about header design, and it is also possible that some power was left on the table for future "development."

However, a better looking header and/or one with more surface area ≠ improved power curves or even higher peak power. A lot goes into factory header design. Witness the mangy, cheap-looking 986 2.5 header. I watched a VERY good race header fabricator make a nice set of stainless headers based on his knowledge from 30+ years of building air-cooled 911 headers. When the car went on the dyno, it lost power. Turns out the factory's funny looking "log" headers with oval, wine-glass inlets had a few tricks up their sleeve.

It's early days for 991.2 Carrera performance. It will be interesting to see how the offerings evolve with time and miles in customer hands.

Valvefloat991

No question that header design is not necessarily obvious. In addition to provide unrestricted flow to the turbochargers, the header should also attempt to keep the individual exhaust slugs separate, as there is a fair amount of pulse energy created when the exhaust valve opens and supersonic flow surges into the exhaust manifold. This pulse energy can help the turbo spool up at low rpm, even when the overall exhaust flow is low. The twin-scroll turbochargers used on most modern turbo engines are designed to separate these exhaust pulses in order to maximize their effect.

RRDnA

How is a dyno result proprietary? It simply shows whether your product delivers a meaningful gain relative to the OEM set up. Moreover, it allows a potential customer to determine whether your product is better than another manufacturers product. Transparency goes a long way in business.

Completely agree, the modelling that goes into some OEM designs is significant - factors such as venturi effect, turbulent flow and pipe friction come into play and are part of a well engineered solution.

///M3THOD

Im disappointed in the product releases Ive been seeing for the 991.2 so far. There's seemingly absent marking department in these companies who put together a cohesive and thorough product release.

Who wants to buy a product at the price point that these systems are without seeing measurable gains verified on a dyno? How about some comments on how they were developed, what their benefits are vs. the stock systems, etc. Theres so little information on this system and all requests for data seemingly go unanswered. Their release video, while beautifully filmed, gives zero information on what the exhaust really sounds like in day to day driving. Thrashing a car around a track doesn't really give you a good sense how loud it is, what it sounds like under moderate acceleration, etc. Its not even detailed what setup is being run.... get it together guys. Its even more disappointing that Kline is likely one of the most well engineered and prestigious systems available.

stout

And that's just it.

I suspect few if any aftermarket companies can match or exceed PAG when it comes to the modeling required to optimize a header (let alone tailor it to various turbos, etc). This assumes, of course, that there aren't gains to be had from areas where the factory was either constrained by component budget, emissions requirements, or long-term marketing/sales planning. While it's early days for 991.2 headers and exhaust, the 991.2 presents a golden opportunity for the aftermarket—and I'm surprised several known tuners have not hit hard with product thus far. I hope we'll continue to see product evolutions and introductions. The only thing I can't deal with is catalyst delete.

RRDnA

Again agreed - the aftermarket industry has so much to add and the ability to innovate which in turn can benefit manufacturers and customers alike. However, in a lot of cases they do themselves no favours.

Part of business success is communication, defining your product, its differences and cost benefit - moreover, if you run a transparent business you can demonstrate the gains a product delivers against known bench marks without divulging key intellectual property.

I have no doubt the series II can be improved, however I suspect its much more nuanced than many appreciate. For example look at the suspension system - even in conventional PASM form its very, very good. In fact, I would go as far to say you would need to go to very high end suspension design and implementation to better it and then you may only better it in specific niches. In fact, in regard to suspension, I would go as far to say a lot of the aftermarket coil over systems would make the current generation of Porsche Sports cars far worse in general terms.