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New Turbo Exhaust - early Christmas Present

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Old 11-03-2012, 11:06 PM
  #46  
speed21
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Originally Posted by Denis with his turbo
You need EP stage 2, not for sensitive ears !

Also I think people should consider this too as it is important (taken from Europipe website): The heatshields around our catalytic convertors allow for quicker heat up during cold start and to prevent them from thermal shocks. The muffler heat shields reflect radiant heat away from the engine timing belts.
You raise a very good point with the heat shielding as well Denis. Additional to the shielding provided on the cats, which is there for very good reason, you also have the heat shielding on the mufflers. This is obviously an essential ingredient for the longevity of certain components in the immediate areas, such as bumper/paint, water pump seals, and front crank seal, rubber belts. I also note Porsches stock system provides the same level of heat shielding confirming it is there for good reason.

How many AM systems out there provide the heat shielding? Not many from what i've seen.... Many seem to get all caught up in the marketing opportunities of claiming a lighter weight in a bid to stimulate a sense of feel good with the purchaser instead of properly designing the system so it actually caters for the cars shielding requirements.
Old 11-04-2012, 05:00 AM
  #47  
Chriss_kline
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An exhaust doesn’t have to be loud or quiet, it can be quiet in the low revs and loud in the high revs. This is how we achieve this.


Every exhaust has a natural latent frequency at which it resonates, this is known as simple harmonic motion or SHM, look the term up, Newtonian physics. Ive never heard of an exhaust manufacturer utilising this except us. Basically we tune the resonance of the exhaust (through cross section, silencer design, and exhaust configuration) to a higher frequency than other exhausts (usually at least 1.5 octaves above other exhaust manufacturers, or 1.5 times the frequency) this has the effect that the exhaust design dampens the bass frequencies associated with low rpm, effectively acting like a shock absorber to the sound waves. In the higher rev regions 5000rpm and above, the engine block, and crank reciprocating frequency become in tune with the exhaust, creating the howl which is associated with kline exhausts, this is also another aspect of performance tuning which other manufacturers do not take into account. Essentially what this means is that kline is the only manufacturer of exhausts that use this principal, and produce exhausts which are quiet in low revs, and loud in high revs. It also is why we get more power!

Basicaly you choose how loud you want to have your car, acording to your driving.
Old 11-04-2012, 06:19 AM
  #48  
speed21
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Originally Posted by Chriss_kline
An exhaust doesn’t have to be loud or quiet, it can be quiet in the low revs and loud in the high revs. This is how we achieve this.


Every exhaust has a natural latent frequency at which it resonates, this is known as simple harmonic motion or SHM, look the term up, Newtonian physics. Ive never heard of an exhaust manufacturer utilising this except us. Basically we tune the resonance of the exhaust (through cross section, silencer design, and exhaust configuration) to a higher frequency than other exhausts (usually at least 1.5 octaves above other exhaust manufacturers, or 1.5 times the frequency) this has the effect that the exhaust design dampens the bass frequencies associated with low rpm, effectively acting like a shock absorber to the sound waves. In the higher rev regions 5000rpm and above, the engine block, and crank reciprocating frequency become in tune with the exhaust, creating the howl which is associated with kline exhausts, this is also another aspect of performance tuning which other manufacturers do not take into account. Essentially what this means is that kline is the only manufacturer of exhausts that use this principal, and produce exhausts which are quiet in low revs, and loud in high revs. It also is why we get more power!

Basicaly you choose how loud you want to have your car, acording to your driving.
I would have thought Porsche would be aware of what you are referring to given they have their own in house sound lab and a team of sound engineers, yet oddly enough their 997tt.1 stock system still manages to exhibit some resonance when the car is in 4th/5th going up a steady incline between 1800 and 3000 rpm, and that's with a system thats legal compliant. So what went wrong there in your opinion Chriss?

Obviously removing 100% of resonance from the new VTG 997 car was evidently a big problem even for Porsche's sound engineers, so logically, it's understandable why 99% of AM manufacturers systems drone, most which are completely unacceptable in my books. And any more drone/resonance than the stock system and the user is bound to have liveability issues at one stage especially if the car is a daily driver.

Now, has there ever been a vendor that openly admits to the potential purchaser that their brilliant 997tt.1 system has drone? Rhetorical question i know, but I think many here know the answer to that one already lol. So, the purchaser is usually left to rely upon vendor/manufacturer assurances. For eg. Ask Tubi does their system drone lol. Actually, i'm not laughing one bit. And, this nonsense about "sensitive ears" is just that....total utter crap. The system either exhibits annoying resonance at 1800 to 3000 or it doesn't, it's that simple. Any system that winds up with some users saying it drones and others saying it doesn't in reality has a legitimate problem...end- of -story.

So Chriss, with respect I assume you have a string of references to vouch your system doesn't drone yet produces miraculous sounds (even obnoxiously loud) on the outside? Seriously, i'd love to add another system to my list that is worth spending money on, because where drone is concerned i'd personally need more than any vendors assurance especially where a 997tt.1 system is concerned....and i'm sure i'm not alone. So a system needs to have a 100% clean slate of users. So, now i ask the hard question, can you back it up?
Old 11-04-2012, 07:02 AM
  #49  
speed21
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Originally Posted by Chriss_kline
I read here about bigger cats and backpressure. Sorry to say but it s completely wrong. oversized cats create more pressure, there is an optimum gas velocity to create the lowest pressure within any closed system, drastic enlargements in cross section actually produce a partial pressure increase, causing turbo lag. for example, yes 3 inch and larger pipe will perform better than stock, but this is not the optimum.
Chris re my remarks to your above quote, in my below quote.

I'm genuinely curious to get your take on perhaps how and why a company such as EP would bother using a larger Dia cat for better flow, yet based upon what you say they evidently mustn't realize their larger Dia cat design is actually stifling flow..... Kinda odd no especially when they have gone to great lengths explaining how their cats offer better flow ( see editorial on cats...http://www.europipe.be/exhausts.html) ?

And then there is the 3" pipe diameter question vs the 2.5. As EP is evidently a specialised Porsche exhaust system only manufacturer, in your opinion why would they go to that trouble if there was no flow benefit with the 3" over and above the 2.5? Any comments or advice for the members?

The other point that has been raised by Denis and myself is the heat shielding. I note looking at your website you don't use heat shielding on your systems either. Comments please?

Originally Posted by speed21
Logarithms aside, I find it hard to imagine EP's larger Dia cats being counter productive in the flow dept. Where pipe Dia is concerned i would have thought a larger pipe would still be better in creating better flow up until such point the air space in the tube/length interfered with the scavenging effect. Anyway.....i'm all ears open.
Old 11-04-2012, 10:13 AM
  #50  
aa909
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Originally Posted by Chriss_kline
Strato58 we use 2.5 pipe size. We also tested with bigger sizes but you loose torque. Our 997tt system with decat hase a 42hp gain, no uprgade on map. Even with hybrid turbo s we still recommend 2.5 inch.
great info. I've read on other threads where folks felt a loss of power (torque) on the lower end but an overall gain in HP at peak. I wonder if what you've shared here regarding the loss of torque with larger pipes as the reason for this lower end loss. is this a general rule of thumb for all aftermarket exhausts for the 997.1TT?
Old 11-04-2012, 10:21 AM
  #51  
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Originally Posted by phillipj
But for someone like me who drives alone (and usually at a rapid rate) 96% of the time, a loud (somewhat obnoxious exhaust (all the time) is what I want.. I don't take my TT on long trips nor am I really concerned about what my wife thinks about the sound. It's my toy and I get to do what I want with it. It don't really care what anyone thinks or what "they would put on their car".. It very similar to wheels.. A very personal choice..

When I'm at WOT my Techart scares the elderly and small children.., Yet is still is not aggressive enough for me. I will do a sound video and post it..
phillip I am with you 100%. I want loud rumble from idle through idle WOT

let me know what you end up getting, I'd love to come down to LA and hear it in person. after wheels an exhaust is next for me
Old 11-04-2012, 10:36 AM
  #52  
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Originally Posted by Chriss_kline
An exhaust doesn’t have to be loud or quiet, it can be quiet in the low revs and loud in the high revs. This is how we achieve this.


Every exhaust has a natural latent frequency at which it resonates, this is known as simple harmonic motion or SHM, look the term up, Newtonian physics. Ive never heard of an exhaust manufacturer utilising this except us. Basically we tune the resonance of the exhaust (through cross section, silencer design, and exhaust configuration) to a higher frequency than other exhausts (usually at least 1.5 octaves above other exhaust manufacturers, or 1.5 times the frequency) this has the effect that the exhaust design dampens the bass frequencies associated with low rpm, effectively acting like a shock absorber to the sound waves. In the higher rev regions 5000rpm and above, the engine block, and crank reciprocating frequency become in tune with the exhaust, creating the howl which is associated with kline exhausts, this is also another aspect of performance tuning which other manufacturers do not take into account. Essentially what this means is that kline is the only manufacturer of exhausts that use this principal, and produce exhausts which are quiet in low revs, and loud in high revs. It also is why we get more power!

Basicaly you choose how loud you want to have your car, acording to your driving.
Sound physics Chriss. Thanks for the explaination. What caught my attention was your mention of a 'howl' which is something I'm still missing in the TT from my former 06 C2S M97. I loved that noise when it kicked in at 4500. Incredible. if you can approximate this I'm very interested.

Where are you guys out of? Cost? PM me if you like but I am sure others are interested too.

Last edited by Zeus993; 11-04-2012 at 11:01 AM.
Old 11-04-2012, 12:37 PM
  #53  
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If you will forgive me for writing a fairly sloppy message, its my Sunday off work, and during the week we work relentless 100 plus hours to make a mark, and develop exhausts of a revolutionary quality.

Are Porsche aware of the scientific concepts that kline utilise within our design process? Without interviewing the guys at Porsche responsible for drafting the exhausts in the design program "catia" this is impossible to answer. What i can say with definite certainty, is that eiesenmann who manufacture the exhausts are not aware of this, and whether or not Porsche are aware is irrelevant. The fact is that their exhausts are not utilising these principals, which is great news, because small operations like kline rely upon innovations which lager corporations either havent considered, or are deemed to expensive to mass produce.

What is important to remember is that,
1) the guys developing exhausts are only human, and miss things from time to time
2)any scientific/engineering discipline is constantly moving forward, the reason is that innovation is constantly outdating old concepts. Consider the lotus monocoque chassis revelation, the big players wished they had thought of that when lotus swept f1. Or exhaust blown diffusers, just a few seasons ago no one had thought of this. The Williams traction control suspension system, the lotus reverse aerofoil floor pan creating venture downforce (incidently this is based on a similar concept to the way we achieve our power gains on turbos), stepped primaries in f1 exhausts utilising sound wave reversion to increase scavenge potential etc etc etc the list goes on.
3) cost of manufacture is prohibitive on design
4) the guys who design exhausts at Porsche are experts in using catia, acoustic modelling software, compressible flow dynamics simulation etc, but these programs will not come up with innovations for you, they will only help quantify the success of your innovation. And the designers at Porsche have only designed a handful of exhausts. Our cheif designer on the other hand has designed and overseen the building and testing of over 5'000 different exhausts over the duration of his career. Incidently we actually work with a major car manufacture to develop their prototypes. The guy at this major manufacturer responsible for first drafting exhausts knows absolutely nothing about the physics associated with designing exhausts, but he is quite adept with catia.

Of course there really is no perfect sound level to suite everyone, one persons drone is another persons quiet, and of course our exhausts are sport exhausts, so are inherently a little louder at cruising speeds than standard. However by raising the note of the exhaust by 1.5 octaves the noise is massively less intrusive, and doesn’t travel through the car so much. At low rpm, an engine is always in a state of equilibrium, the counter forces (friction on moving parts conversion of kinetic energy to thermal, sound etc) are in balance with the amount of kinetic energy being derived from chemical potential energy within the fuel. Therfor at low rpm, low quantities of fuel, result in lower KE output, and if you assume that an increase of kinetic output is proportionate with an increase in sound energy. Therfor low revs and low throttle are associated with less noise losses, or sound output of an engine. What im basically saying is high revs hard throttle is an engine produces a lot of noise, low revs low throttle does the opposite, so an exhaust that is well designed should be quiet when driven softly, and loud when driven hard. Drone is usually associated with incorrect cross sections

What makes us so confident about our exhausts is really quite simple. Our engineers have been working in this field for so long that they can instantly pull apart any design flaws in any exhaust, and believe me every exhaust has design flaws. And secondly because almost every customer who we have sold an exhaust to, contacts us within a day or so of fittng raving about how amazing the sound is compared to other exhausts they have tried, we have never had a dissatisfied customer.

If you like i can confuse the hell out of you with hundreds of pages of mathematical derivation explaining our concepts, and they will be tough, i am a quantum physics graduate with a taste for thermodynamics and compressible fluid dynamics.

We are so confident we offer a 28 day satisfaction guarantee!

Any other questions please ask or PM me.
Old 11-04-2012, 12:56 PM
  #54  
Bob in NY
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Wow! Here is a non technical question. Is it possibe to hear your system for the 997 Turbo? Do you have a clip on You Tube or have a dealer in the NY area? Thanks.
Old 11-04-2012, 01:05 PM
  #55  
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Here is a soundclip


Not the best recording. You can also here it on our web site kline-innovation.com

We dont have a dealer but you can buy direct from us. We can ship with TNT, 2-3 days.

You are welcome!
Old 11-04-2012, 01:24 PM
  #56  
Bob in NY
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The sound clip on your web site doesn't appear to be working
Old 11-04-2012, 01:33 PM
  #57  
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On 997 tt pres play and wait 2-3 sec, dosen t start right away. Our website is still under construction, it s not 100%
On my computer it works.
Old 11-04-2012, 01:35 PM
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Sorry, forgot to reply to heat shielding question.

Pressure and temperature are in a state of equilibrium according to the laws of thermodynamics, much like pressure and velocity are inversely proportional in compressible fluid dynamics, if you alter one you get an opposite alteration to the other, albeit through a couple of constants. Higher gas velocity results in lower pressure, lower pressure results in a lower temperature ( well not exactly, the lowering pressure wants to shift the equilibrium in favour of higher temperature) but what this means is that the lowering pressure of the exhaust gasses tries to reach energetic equilibrium by drawing heat away from its surroundings, essentially cooling the periphery of the exhaust. This is also how a fridge works, cooling across pressure differentials. Because our exhausts are not chambered like oem, and some am systems, and because we use tuned cross sections, the exhaust remains cooler than standard so heat shielding is not required. Heat shields on cats are used to bring cats to a higher threshold temperature meaning less rheubidium and platinum are required, and are really nothing to do with protecting your car, but we like to keep things simple!

If you like, YOUR KLINE can build a system with heat shielding, we can laser cut you a beautiful heat shield with an inscription if you so desire! We have a special area on our website explaining that you can have your unique system. Made from stainless or INCONEL 625, formula 1 Grade.
Old 11-04-2012, 01:38 PM
  #59  
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Originally Posted by Chriss_kline
On 997 tt pres play and wait 2-3 sec, dosen t start right away.. On my computer it works.
hmm, guess it's on my end. no worky for me. Can you PM me with est cost of the system or post here.
Old 11-04-2012, 03:53 PM
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Originally Posted by aa909
phillip I am with you 100%. I want loud rumble from idle through idle WOT

let me know what you end up getting, I'd love to come down to LA and hear it in person. after wheels an exhaust is next for me

You let me know when you'll be in the area and we"ll set a drive! Can't wait to see your wheels..


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