Europipe EP1 or Akrapovic??? Can't decide!!!
#34
Funny, I was at Europipe having my exhaust installed by Stef and Herman.
They greeted me, looked over my car as 2 enthusiasts and shortly after they started working on my car. If I would not have asked questions after that I believe not much would have been said. They don't talk, they DO !
But the curious guy I am I started to ask questions. I am always interested how people started out so I asked. Turns out Herman was unhappy with cracking headers on his Porsche 914/6 and decided to make them himself. Other people with similar problems took note and asked if he could do something similar. Later he became known in the racing car business and was approached by several teams to make headers and exhausts. His exhaust were so good he soon became the 'go to' man for big teams. In fact, cars equipped with his exhaust and headers were very successful. But as I said, they don't talk, they DO !!
So his reputation was build from mouth to mouth, not from advertising, big claims, or a fancy name. And to this day they still work like this.
Europipe is a 2 man show and that is what they want it to be. They have the knowledge and technology to be 'big' but have no desire too.
So before you make claims there is no comparison just know that there has gone A LOT of research in a Europipe but the communication about it is absent. And frankly, they do not need it as they have plenty of orders and are busy. Maybe it is a Belgium thing
They greeted me, looked over my car as 2 enthusiasts and shortly after they started working on my car. If I would not have asked questions after that I believe not much would have been said. They don't talk, they DO !
But the curious guy I am I started to ask questions. I am always interested how people started out so I asked. Turns out Herman was unhappy with cracking headers on his Porsche 914/6 and decided to make them himself. Other people with similar problems took note and asked if he could do something similar. Later he became known in the racing car business and was approached by several teams to make headers and exhausts. His exhaust were so good he soon became the 'go to' man for big teams. In fact, cars equipped with his exhaust and headers were very successful. But as I said, they don't talk, they DO !!
So his reputation was build from mouth to mouth, not from advertising, big claims, or a fancy name. And to this day they still work like this.
Europipe is a 2 man show and that is what they want it to be. They have the knowledge and technology to be 'big' but have no desire too.
So before you make claims there is no comparison just know that there has gone A LOT of research in a Europipe but the communication about it is absent. And frankly, they do not need it as they have plenty of orders and are busy. Maybe it is a Belgium thing
#35
1. Cross section: I would think resistance of conduit is determined by a few parameters, not just cross section: resistivity (of the cat, the pipe, etc.) x length (of the cat, the pipe, etc.) / cross section.
You could have a large cross section, but if you stuff sand in it (high resistivity), the resistance will be sky high. In addition no one has mentioned this but the length of the cat is a factor (check the picture of the cats, which one is longest?). Lastly, the sound muffler also affects resistivity. Until you know all the parameters involved, you cannot make any claim merely from the cross section.
2. Cross section and EGT: The Europipe exhaust is of course expected to reduce EGT, but if you are stating that it is lowest **in comparison** to Akrapovic, or any other exhaust: even Stef is careful never to make this claim. If you have convincing proof I would love to see it. Check the Europipe web site, rightly VERY little is claimed: http://www.europipe.be/exhausts.html
3. Cross section and lower back pressure: This is the one and only test I am aware of by Europipe that compares EP to other exhausts, but... even the result of this test was questionable because boost pressure was not measured at same time as back pressure. The lower back pressure could be from lower boost. Bottom line is despite of certain expected results, very little have been proven convincingly.
Europipe is an outstanding exhaust, with excellent sound and craftmanship, enjoy it. But if you are trying to place your EP2 above Akrapovic on technical merits, first consider the technical development of Europipe vs. Akrapovic (multi gears, partial throttle, full throttle, in house dyno, etc., see ad material here http://www.akrapovic.com/en/technolo...s/default.aspx), in addition to the pedigree (Audi Le Mans, Manthey Racing, Porsche cup, etc.) and history. Sorry but there is no comparison whatsoever.
You could have a large cross section, but if you stuff sand in it (high resistivity), the resistance will be sky high. In addition no one has mentioned this but the length of the cat is a factor (check the picture of the cats, which one is longest?). Lastly, the sound muffler also affects resistivity. Until you know all the parameters involved, you cannot make any claim merely from the cross section.
2. Cross section and EGT: The Europipe exhaust is of course expected to reduce EGT, but if you are stating that it is lowest **in comparison** to Akrapovic, or any other exhaust: even Stef is careful never to make this claim. If you have convincing proof I would love to see it. Check the Europipe web site, rightly VERY little is claimed: http://www.europipe.be/exhausts.html
3. Cross section and lower back pressure: This is the one and only test I am aware of by Europipe that compares EP to other exhausts, but... even the result of this test was questionable because boost pressure was not measured at same time as back pressure. The lower back pressure could be from lower boost. Bottom line is despite of certain expected results, very little have been proven convincingly.
Europipe is an outstanding exhaust, with excellent sound and craftmanship, enjoy it. But if you are trying to place your EP2 above Akrapovic on technical merits, first consider the technical development of Europipe vs. Akrapovic (multi gears, partial throttle, full throttle, in house dyno, etc., see ad material here http://www.akrapovic.com/en/technolo...s/default.aspx), in addition to the pedigree (Audi Le Mans, Manthey Racing, Porsche cup, etc.) and history. Sorry but there is no comparison whatsoever.
#36
The worth of an exhaust is therefore, not measured only under WOT and one single test cannot reflect its performance. IMHO partial throttle, multi gear test, etc., is at least as important, if not more, for cars not at the race track 100% of the time. That is why the testing claims of Akra so impress me. It is the one and only company that brings up these issues that answer my questions. I don't want to get into hot water any more :-) but compare the tests by one company (dyno, pressure) to the other, then you could see why for your GT2, there are 8400 reasons to go Akra.
I am making my posts deliberately provoking/challenging so any expert could jump in and correct me and we could all learn. Even if I am heavily criticized and proven wrong, we would all learn something on this un-necessarily mysterious topic. I hope I don't get EP owners too upset (please relax and enjoy your EP). Really, a while ago when FVD was stating their exhaust is "true" quad pipe, I also questioned the claim; I am not picking on any one company!
Last edited by cannga; 08-22-2012 at 10:18 PM.
#37
Europipe - Akrapovic
So the quality of our Europipe exhausts is so low that you can't even compare it with the Akra? I take that as an insult.
You downgrade our exhausts yet within the same day I receive your order for our 997.2 Turbo S exhaust.
Sorry but I'm no longer interested in your business.
You downgrade our exhausts yet within the same day I receive your order for our 997.2 Turbo S exhaust.
Sorry but I'm no longer interested in your business.
#39
It is very odd that you are taking my comments this way. In fact, I suggest you re-read my post and point out to me where I am mentioning anything about low quality of Europipe exhaust units.
My point is that you cannot compare a stainless steel exhaust to a titanium exhaust. They have different manufacturing techniques and final weight. Akrapovic makes stainless steel exhausts for other cars but not for Porsche. If they made a comparable exhaust for Porsche in stainless, there would be a direct comparison.
Ultimately it is your choice on how you want to take my comments; however, I feel that I was objective and positive towards both brands.
My point is that you cannot compare a stainless steel exhaust to a titanium exhaust. They have different manufacturing techniques and final weight. Akrapovic makes stainless steel exhausts for other cars but not for Porsche. If they made a comparable exhaust for Porsche in stainless, there would be a direct comparison.
Ultimately it is your choice on how you want to take my comments; however, I feel that I was objective and positive towards both brands.
#40
Seriously, I think Stef got it right. The way your words are formulated make it crystal clear Europipe is no match for Akrawhatever.
I hate it when vendors discredit products, usually because margin is bad or they can't have it.
I would prefer the end consumer to do that as a neutral 3rd party.
#41
My point is that you cannot compare a stainless steel exhaust to a titanium exhaust. They have different manufacturing techniques and final weight. Akrapovic makes stainless steel exhausts for other cars but not for Porsche. If they made a comparable exhaust for Porsche in stainless, there would be a direct comparison.
I read your post the same way, as if the Akrapovic was somehow better quality because it was made of a different material. This is obviously not the case. Titanium has the obvious advantage of being lighter for a given strength, but Stef's exhaust has some very compelling design aspects, such as larger piping, larger cat cross sections, tuned chambers, proper head shielding and an OEM-style look. I would have reacted the same way that he did if it were mine.
#42
while manufacturing techniques are different, the design is similar. Titanium is lighter and has different resonant frequencies, but the end result from a power and sound point of view are directly comparable.
I read your post the same way, as if the Akrapovic was somehow better quality because it was made of a different material. This is obviously not the case. Titanium has the obvious advantage of being lighter for a given strength, but Stef's exhaust has some very compelling design aspects, such as larger piping, larger cat cross sections, tuned chambers, proper head shielding and an OEM-style look. I would have reacted the same way that he did if it were mine.
I read your post the same way, as if the Akrapovic was somehow better quality because it was made of a different material. This is obviously not the case. Titanium has the obvious advantage of being lighter for a given strength, but Stef's exhaust has some very compelling design aspects, such as larger piping, larger cat cross sections, tuned chambers, proper head shielding and an OEM-style look. I would have reacted the same way that he did if it were mine.
You forgot to mention, titanium fatigues much quicker then stainless steel, due to its strength, it brittle's. Kit, if you are still interested in the ebw exhaust , I have a very nice offer for you : ) lmk.
Enrique
#43
Hi Bob. Sure, but the problem is this: which data? For example, the dyno? First we all know dyno's could be manipulated, so it is impossible to be fairly compared. Second and more importantly, what is the dyno test? It's a single 4th gear, wide open throttle test. But... how often anyone of us, particularly in the Turbo, runs our car at wide open throttle in fourth gear when used as a daily driver? I would say lucky if it's even 2% (you should be in jail otherwise doing this on regular streets LOL). The majority of the times, the Turbo is used other gears; the majority of the times, it is under partial throttle controlled acceleration, etc. Of course the dyno is important, but it cannot be the only test.
The worth of an exhaust is therefore, not measured only under WOT and one single test cannot reflect its performance. IMHO partial throttle, multi gear test, etc., is at least as important, if not more, for cars not at the race track 100% of the time. That is why the testing claims of Akra so impress me. It is the one and only company that brings up these issues that answer my questions. I don't want to get into hot water any more :-) but compare the tests by one company (dyno, pressure) to the other, then you could see why for your GT2, there are 8400 reasons to go Akra.
I am making my posts deliberately provoking/challenging so any expert could jump in and correct me and we could all learn. Even if I am heavily criticized and proven wrong, we would all learn something on this un-necessarily mysterious topic. I hope I don't get EP owners too upset (please relax and enjoy your EP). Really, a while ago when FVD was stating their exhaust is "true" quad pipe, I also questioned the claim; I am not picking on any one company!
The worth of an exhaust is therefore, not measured only under WOT and one single test cannot reflect its performance. IMHO partial throttle, multi gear test, etc., is at least as important, if not more, for cars not at the race track 100% of the time. That is why the testing claims of Akra so impress me. It is the one and only company that brings up these issues that answer my questions. I don't want to get into hot water any more :-) but compare the tests by one company (dyno, pressure) to the other, then you could see why for your GT2, there are 8400 reasons to go Akra.
I am making my posts deliberately provoking/challenging so any expert could jump in and correct me and we could all learn. Even if I am heavily criticized and proven wrong, we would all learn something on this un-necessarily mysterious topic. I hope I don't get EP owners too upset (please relax and enjoy your EP). Really, a while ago when FVD was stating their exhaust is "true" quad pipe, I also questioned the claim; I am not picking on any one company!
I know that there are several tuners that will report that their exhausts support XXX hp - while I don't doubt that, I guess I'd like to see a backpressure number - it's the only number that can be compared objectively and in a way that even I can understand.
#44
Because utilized boost is essentially the difference between what is demanded and the backpressure, I guess the backpressure number would be the most important number that I'd like to see. The only two companies that I know publish this info is Europipe and AWE.Props to both for sharing info.
ENGINE CYLINDER---A---TURBINE---B---CAT CONVERTER---MUFFLER
AWE's boost pressure is at A (anyone pls correct as needed)
EP's direct pressure is at B
As mentioned, the measurement method by EP has also been questioned: measuring backpressure at B is meaningless unless you measure/control the boost pressure at A because if A increases, it causes B to increase. This was not done in EP's measurements. This is especially relevant when the difference is small, says between 2 after-market exhausts using 200 vs. 100 cpsi (as opposed to stock). Is this uncertainty why no other company mentions this measurement?
Besides the issue of which number to use as pointed out above, the danger of using a single number is that it could be very easily distorted like dyno number for advertisement purpose ("my back pressure is lower by 0.3 psi so therefore it's better" - there is no proof of this among AM exhausts). Back pressure is important yes, but this single gear, WOT testing tells you nothing of the whole operating range of the engine from 3000-6000 rpm. The system, engine, header, exhaust, turbo work together as a whole, we know about the importance of scavenging effect for example, and Akra's test claims, to me exactly illustrate this point. There is no mention of back pressure being the end-all be-all, just multi gear, partial throttle, controlled acceleration, etc.
Last edited by cannga; 08-24-2012 at 01:59 AM.
#45
Remember that boost is coming into the cylinder head and is separated from the exhaust side by the combustion cycle. While a freer flowing exhaust may cause more transient boost, the boost targets in the ECU aren't changing, so the delta in boost pressure is small. And, it's not directly correlated to backpressure, because there is a combustion event in between... (yes, there is more than likely a bit of valve overlap, but not a huge amount... and more boost would cause more backpressure not less.)
Key points is that you'll usually see the highest backpressure at the point of highest volumetric efficiency for the motor. This is likely not the point at which boost peaks. I think Europipe's measurement is perfectly salient.