BC-997

I'm about to order a Sharkwerks bypass kit and compared it to the AWE kit. Sharkwerks talks about a 12 - 15 HP gain at the wheels while AWE cautiously says their bypass pipes will get you 5HP.

The systems are about the same price and they look like they are shaped similarly. Does anyone know why they perform so differently?

Thanks
Greg

onedae

I wouldn't make your decision based on the additional HP claims - they are questionable at best. I've heard both the Sharkwerks and AWE center bypass pipes and both add a modest amount of sound, but each a slightly different tone. I got the AWE as it was a little deeper and less raspy to my ears. Either one is nice. But if you're looking for more power, this is not the way to go.

Skibum

They are both just pieces of pipe.
If you were being obsessively ****, I would choose the pipes that have the smoothest bends. (Sharkwerks)

IMHO of course.

kosmo

+1000

If you want real world gains, get a FULL intake, Full exhaust, and ECU reflash. Otherwise its just masurbation.

tcouture

I have the Sharkwerks and I think it is a great mod for the money.

That being said, like the previous posters say, I think you should base your decision on sound, not HP as I could not feel any difference in pull.

But I do find the sound noticeably better and faster .

T.

BC-997

Thanks everyone. I'm really just interested in a modest change in sound. I think the center muffler is quite restrictive and gives the car somewhat of a rattle sound at low rpm. I just want to smooth that out and give it a lower tone. I can always keep modding if it doesn't improve much.
Cheers
Greg

Skibum

I believe that that rattle comes from the baffles inside the mufflers. Not sure...
It drove me nuts.
If you're still looking for a more deep mellow sound check into the Borla muffler.

Dan@SharkWerks

Hi guys, interesting topic here and it notifies us when our name is mentioned so I thought I would add my experience to this.

I can't speak for AWE, but in terms of how we dynoed our car, I truly believe the gains we had were genuine (12 RWHP) using the center section we designed.

We brought our 2009 PDK Carrera S to Stasis Engineering (an Audi tuner that had a mechanically linked all-wheel-drive Mustang Dyno) in northern CA, as we do not have a dyno in-house. It was the first time they had met us and I don't believe they would skew the results just to please us.

This was our dyno process:
Stock car is dynoed until the power peaks (about 3-5 dyno pulls). Eventually the motor will heat soak and the power gains will drop slightly (1-2 WHP). We use the peak power before this happens as our baseline. This was 309 HP, 244 ft-lb torque. These numbers might seem low for a 2009, but remember this was on an All Wheel Drive dyno. And our main point of interest was the delta between the two systems.

We switched out the exhaust while the car cooled down, then re-dynoed.
The initial dyno did not show a gain in power, as the ECU had not adapted yet and the car was not at its ideal operating temperature.
After around 8 dyno pulls, the numbers peaked again and started to fall off by 1-2 WHP. The numbers were 321 and 255, or 12 HP higher and 11 ft-lb torque.

Here is the dyno graph:


Our goal was to show there was not a power loss from our exhaust, we were not expecting a power gain and were very happy when we made more power from it.
From looking at the design of the stock exhaust, you can see why it would help the flow to replace it with a system such as ours: the stock system makes a complete 180-degree u-turn on either cylinder bank before entering the side mufflers. Our system is a straight-through mandrel bent (equal diameter) tube.


I have not personally dynoed a 2009 Carrera with a full exhaust, but as the stock headers and cats are single units, I would leave them alone and only change the side mufflers if anything, but I don't think you'll see an additional 12 HP to the wheels from changing it out.
Also, the intake on these cars is quite good from the factory and it's a nice sealed system that does not suck in hot engine air, so I think you'd be hard pressed to make signficant improvements on it.

The only other change I've seen that makes quick power gains on these cars is the ECU mapping. The factory does a great job tuning the car for all markets, reliability, emissions and fuel economy. When tuned for performance we squeezed out another 14 HP to the wheels, 9 ft-lb, more aggressive throttle response (which makes the car feel faster and more responsive) etc:

http://www.sharkwerks.com/products.php?pid=200

For more info on how we did the software tuning, please see this write-up:
http://sharkwerks.com/porsche/techni...s-ztadpol.html

Skibum

Excellent post.
Thanks Dan.
One question I've had is how long does it take the ECU to "learn" an exhaust change and what is the best way to "teach" it?

Dan@SharkWerks

The dyno makes it easy because we can do 0-150 MPH about 10 times in 10 minutes without getting a speeding ticket.

For most people with regular and occasional WOT driving, it will probably take about 30-60 miles for the ECU to adapt on these cars. If I understand it correctly, each time you do a WOT "pull", the ECU will attempt different fuel and timing maps, checking O2s and knock reading etc to try more aggressive settings until a plateau or safe limit is reached.

Here's a little video Alex made documenting what Todd does to modify the maps realtime:
http://www.youtube.com/watch?v=JJw8QFp3fVI

BC-997

Thanks Dan. You have answered my original question. As I said, i wasn't really doing this for HP gains but if I got some- bonus! I was just confused by the differing claims.

I'll be putting in my order in the next couple of weeks and have Weissach install it for me. Thanks for your help.

Greg

pcostinha

My experience is with FABSPEED products (USA).
I have the X-pipe from Fabspeed since last year and it is fantastic. With only +5 dB compared to the OEM but the type of sound is very good, such that other owners of 997.2 ask me where I bought it.
This week I add in the car the Valvetronic also from Fabspeed. This exhaust is impressive. With valvule closed, have a nice sound (low frequency), much better than OEM exhaust.
When we change to open valvule (by wireless), when we strong acelerate, is like a F1... (inside of the car we don't know what happen outside - this is what the people said when I pass by them).
About Hp and Torque I feel that have much power (about 20-30Cv) and more important for me much more Torque (about 38 ft-lb).