I have BBI stage II. Exhaust sound is very important to me so I went with a louder and deeper sounding system to emphasize the sound. There's definitely a level of drone in the cabin at crusing speeds which can reduce the comfort level on long drives but if you can deal with that, I'd definitely recommend. Sounds lawesome from 3500rpm on up.

 

No money is owing stef. Your exhaust is more than enough. It was just good to finally get what i paid for. That doesn't happen too often these days so i am more than satisfied with just that and if i can help others from not making the same mistakes i have made then that is a bonus.
And speed21? Stef you are correct that it stands for something.....quite a lot actually but i must keep that a little secret for now.

So after the two cars lengths is gained the two cars move at the same rate? I would have thought the EP car would continue to edge away?

Thanks my greek friend. I understand Skand is also now a EP convert as well! Good to see the greek guys are getting in the know! Enjoy...as i am.

Sorry to hear that RossoX2. Yes learning to tolerate something like that is thankfully not necessary with the EP system. I found my previous AM system was like that. It was a bit like fitting a millstone around your neck. It will eventually bring you to your knees. With EP you just get the good noise outside and nice spool inside with no annoying drone or resonance.....and the nice power benefit as well. EP = Sound + Power, minus the headache .

 

The best sounding loud exhaust on the market with 200cell cats is the FVD sound version without a shadow of a doubt!


There are lots of loud exhausts but none that sound as good as that IMO!

Either way just make sure you hear a few before you spend your hard earned cash.

 

Does that FVD come with or without millstone? Most don't seem to have the millstone supplied in the kit....probably gives the game away before install.JK.

PS. OP has already pulled the trigger on the speed art. Review pending.

 

Some interesting reading, for anyone interested. Low end torque loss has been reported by just very few people with after-market exhausts, but, IMHO (based on extensive "web" research LOL) the issue is real and brings to mind that whatever we do in our system, there might be some trade-off involved. Too much reduction in back pressure could hurt the system at low rpm. (This applies to all systems, not anyone in particular.)

Report of absolute power gain is deceiving, because it only tells you one point of the dyno curve. The only way is to examine the *shape* of the curve and gains at low rpm and at high rpm. The max gain may come at, say 5500 rpm, but what happens at 3200 rpm, when boost is low?

BTW, for the very little gain reported by various after-market exhaust systems, a good test of power gain is, especially, *not* to race two different cars (way too many variables - just read any ECU tune thread), but to do Vbox proven timing runs of same car before and after. 20 hp gain, I don't believe proof will come easy. I am not even sure chassis dyno is ideal (better than nothing, but not ideal) because the 20 hp gain that most tuners report could even be a result of run differences. One would think engine dyno is the only way.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
http://en.wikipedia.org/wiki/Scavenging_(automotive)
In automotive usage, scavenging is the process of pushing exhausted gas-charge out of the cylinder and drawing in a fresh draught of air ready for the next cycle.
This process is essential in having a smooth-running internal combustion engine. Modifying the exhaust system, (i.e. modifying the exhaust gas velocity by changing exhaust tube diameters) can detract from the "ideal" scavenging effects, and reduce fuel efficiency and power if not properly planned out and executed.
To increase scavenging potential, the entire path from intake to exhaust (i.e. all powertrain parts) to tailpipe must be tuned in sync with each other. This will ensure that the air flow is never interrupted. The acceleration and deceleration of this exhaust gas is what will hinder the scavenging potential.
For example, fast flowing heads and a tunnel ram intake combined with a badly planned camshaft and exhaust system will cause the air to "slow down" and "speed up" throughout its journey, thus reducing its scavenging potential. So, to increase scavenging potential, the air must maintain a positive linear acceleration curve.
...

 

I know how ! It took us several months and 19 different prototype mufflers to make it sound like that. Actually 19 different muffler cans because the 100 cell cats and the rest of the design was fine from the beginning.
Some of these prototypes were real Dronemasters but I'm proud that we didn't give up.

Enjoy your car Bernd !

 

Can no offence but i don't need two cars running side by side or any dyno to know the difference between the EP i now have on and the previous AM system i removed. The difference is unmistakable....like the car became slippery like never before....even VS with the stock system on which has asthma down low. When i drove the car in that morning, and then doing the exhaust change out and then afterward driving the car home the very first thing i noticed was the car felt oddly slippery and eager to go. It was like wtf!...Am i imagining things? So a few more acceleration tests at different points in the rev range on the same stretch of backroad i drive every single day confirmed without any shadow of doubt the car was pulling cleaner and stronger right through out the rev range...time after time,... it was quite addictive, and proof enough for me and i am a very vey hard critic of these things. I wasn't even looking for this improvement as it was not really a goal at that time. Getting rid of drone was my main objective and, without losing power. So, the next morning, i found the same thing again. The bloody thing was flying like never before. In fact the car was pulling so clean and hard i didn't even bother loading the damn tune in until a couple of months later. There was no need. So, you can basically pull all the crap off the web you can muster but it won't change the way the car goes better and, WITH the stock tune. And now, with the tune loaded up it's even more ridiculous!!....crazy fast!!. I would agree that most of the exhausts out there seemingly need a tune to hide behind (like the system i took off) but not this EP. It definitely works 100%. So with regard to the perfect balance required to achieve the right outcome on an exhaust system, i can assure you stef has clearly established the right recipe here...no question about that. But thats ok. Don't believe me. I can handle it after all I know I'm the lucky one with the EP on.

 

For what it's worth on the 997.1tt of all the exhausts I've done over the years the best fit (every time) is the EP. It sounds really good too and the stage 1 has no resonance. For any one concerned with too much interior drone it's the best solution since it has none. Exterior sound is really good too. In terms of having something louder and _with_ some drone (to some acceptable and others not) the Tubi and Cargraphic are second. Tubi is lighter, has better fit and higher-pitch tone. The Cargraphic is a deeper tone and has a great rumble. The only other thing with the later is the manufacturing isn't what I'd call top notch. It's made in the UK so... fitment is annoyingly different depending on which batch. Could be easier to install but worth the trouble once it's on.

 

I just finished putting FabSpeed dual exhaust tips on my EP and all I can say is...WOW...didn't think the sound could be better but boy was I wrong...love, love, love it, pure music....and on top of it they are drop dead beautiful...

 

Paul, I don't question anyone's subjective evaluation and trust & believe your impresssion! My discussion is not about whether your car *feels* faster w/ EP than w/ xxx, but whether it is *objectively* faster, than a stock car. About methodology.

I was referring to Stef's methodology - saying that his car with Europipe exhaust pulls 2 car lengths ahead of another car with stock exhaust. Any cursery look in any ECU tuning thread will tell you that this is the least desirable way of proving power/acceleration increase. The difference could be due to a. drivers' skills, b. other car being slower than Stef's stock car to begin with; essentially too many variables. The importance of correct methodology is the basis of this landmark thread in the 996 Turbo forum: https://www.6speedonline.com/forums/...le-thread.html

In short, subjective: anything goes, objective: there are 3 ways:
1. Vbox timing runs before and after.
2. Chassis dyno before and after.
3. Engine dyno before and after.
Number 1 is sort of the bottom line but is going to be very difficult to prove I think with a 20 hp increase. Number 2 also, the difference of 20 hp is difficult to prove IMHO - possible, but difficult. That leaves number 3, and I am fairly confident this is how Porsche tunes its exhaust. Little difference like this is most reliably shown with engine dyno, I would think (anyone pls correct as needed).
In addition, as important as absolute power gain, is the shape of the dyno curve. Power gain at 6000 rpm is good, but what happens at 3200 rpm, where boost is low? Will the the reduced back pressure cause power loss at low rpm from the reduction in scavenging potential?

 

You need to hear a X-flow design system from 911tuning or SpeedTech...

 

We bought our 997 Turbo back in october 2006 and a friend of us took delivery of his Turbo later that year. Ours came with Bridgestone tires while his Turbo ran the noisier Michelins.
Both cars were dead even during acceleration test, we usually started at around 60-100 km/h to whatever speed was sane.

We kept racing each other during the following months, his car remained stock while ours had all kind of prototype mufflers. It was during these tests that we first noticed the quicker acceleration of our car.
The better acceleration is not due to the increased output at around 6000 rpm but because of the higher output at low rpm and midrange and also because of the much better throttle response.

The better throttle response is something that you can't measure on an engine dyno. The Vbox runs and the dyno results aside , we have dozens of happy customers who feel that their car becomes quicker with the aid of our sport exhaust.
Read some of these: http://www.europipe.be/testimonials.html

The only reason for the better performance with our sport exhaust is because of the lower backpressure.
Most anything you'll read on the internet about low backpressure and torque loss refers to NA engines.

Why is there a torque loss with straight bypass pipes on a Turbo? Well not because of the low backpressure but because of the short lenght pipes.
If you want low backpressure without the torque loss then go for long lenght bypass pipes. Some tuners like Todd K offer these.

Hope this info helps.
Cheers, Stef

 

Thanks Stef for taking the time to explain. I've been told where there is no boost or low boost, below say 3000 rpm-3200 rpm, the Turbo engine takes on some characteristics of a NA engine, hence scavenging effect is important. Not accurate?

This low end power loss w/ after-market exhausts has been observed by just a couple of people here. The three I know of affects 3 different brands. The subjective and anecdotal nature of the power loss observed makes accuracy debatable, but it *has* been observed. AFAIK, there has only been one before and after dyno's done by user (ie not ad material by vendor) on this forum, and that dyno showed reduce power at low rpm. I asked owner to post but he never did. Again, one study is hardly conclusive.

Important point is for readers to know that the sense of low rpm power loss has been reported with after-market exhausts. Whether or not it is due to scavenging effect? It would have been nice to have some explanation. BTW, congrats on your success; from users' reports, I don't have any doubt about the construction and quality of Europipe. I also enjoy reading your many informative posts.

 

I always thought if I got a TTS I would definitley get the europipe. But with the 997 GT2 I have not heard anyone comment on preferrable exhausts. Someone is offering to sell me there slighly used GMG exhaust for half the price of new, and said it sounded great on his GT2. Do not want any drone and do not want to spend 9k on the Akropovic.
Anyone with some experience on this?

 

My pleasure Can and you're correct about the NA engine characteristics of a Turbo engine at no boost. If you watch the boost gauge on your dashboard you'll notice that there is zero boost from idle to about 5000 rpm when you accelerate slowly. The scavenging effect on a turbo engine is much smaller compared to a NA engine though as the coherent air flow is ruined by the spinning turbowheel itself.
Also note that dyno's measure torque ( which is converted to hp ) at Wide Open Throttle only. An engine can perform brilliant at full throttle but might perform not so brilliant at part throttle. I'd rather drive a turbo engine with a crisp throttle response, lots of torque at low rpm and midrange combined with a strong top end than to go for a fancy high hp engine that snaps your neck at 5000 rpm but lacks drivebility at part throttle.
So you can't judge an engine solely by its dyno result.
I haven't encounterd torque loss on any of our Turbo exhausts yet. (knock on wood) Never heard complains about other aftermarket turbo exhausts either.

Cheers, Stef