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I've got PSE and the rear center muffler delete, I'm very happy with that, and it's loud enough for me. Certainly start up is pretty loud.
If I wanted more performance, I'd swap out the headers and cats but then it might get a lot harder to pass my local emissions requirements. I have that issue on the other car, which has motorsport headers and a high-flow sports cat. It needs to be red hot...
Just curious, you deleted the center muffler. What did you replace it with? Can't just remove it as far as I know.
It's amazing, everyone without exception is very happy with Shark Werks Sport Exhaust Cross-Pipe - and I understand it remains the best sound. good to hear.
At the same time, I am missing one thing in this whole equation and I would love an explanation. In 997.1 Porsche engineers designed a Cross-Pipe with converters.
Over the years to improve sound and performance (I'm not talking about 'Fister'), the most popular improvement in 997.1 and the most noticeable was to change it to X-PIPE with 200CELL converters (or without converters but I do not recommend it).
Years passed, and here, in 997.2, Porsche's engineers changed the design (moved the converters to the headers area and instead of Cross-Pipe, they pre-designed X-PIPE (in central exhaust).
Now I ask - is it right to "go back" in 997.2 to Cross-Pipe?
(By the way, fabspeed is still producing for 997.2 X-PIPE and not Cross-Pipe but I read that the sound is very similar to PSE and the change in sound is not noticeable).
So what is the most engineeringly correct? Cross-Pipe or X-PIPE?
If Porsche chose to do X-PIPE after hours of planning and engineering, why do we go back in 997.2 to the Cross-Pipe configuration?
Thoughts
This is confusing to me. The 997.1 doesn't have a center muffler so no need for cross pipes. I was always under the impression that it basically had one set of headers, a cat and one muffler for the left and right bank of cylinders respectively. No connection between the two with "converters" or otherwise. The exhaust mod on my -06 C4S was simply two Tubi mufflers. One for each side. Nothing else and the sound was absolutely amazing.
Not that it really matters but just curious what I have missed over all these years in terms of how the .1 car's exhaust system was designed.
This is confusing to me. The 997.1 doesn't have a center muffler so no need for cross pipes. I was always under the impression that it basically had one set of headers, a cat and one muffler for the left and right bank of cylinders respectively. No connection between the two with "converters" or otherwise. The exhaust mod on my -06 C4S was simply two Tubi mufflers. One for each side. Nothing else and the sound was absolutely amazing.
Not that it really matters but just curious what I have missed over all these years in terms of how the .1 car's exhaust system was designed.
I will try to be a little clearer.
In 997.1 there was originally a cross pipe (with or without converters) and the common upgrade among the leading companies was to change the modification to x pipe:
Years have passed, and in the original 997.2 it is x pipe (called "center muffler") and now we are "going back" and changing back to cross pipe mode (For example Sharkwerks - with the best sound as I understand it):
*** Note that some companies in 997.2 still chose to replace the original "center muffler" with an improved x pipe. For example Fabspeed / Soul:
Cross-pipe is definitely better because you remove the 180° U-turn tubes and reduce the loss of flow.
I don't know if you save 12HP at wheels like Sharwerks says but you save power for sure !
With the Flat6 engine it's not necessary and not advised to have connexion between the 2 exhaust banks like we can see on the X-pipe type (only with mechanical point of view)
In fact when you install a cross-pipe on a 997.2 you restore the flow and the sound of the 997.1. The only difference after cross-pipe installation on 997.2 is that the cats are on the exhaust manifold on 997.2 and on the cross-pipe on the 997.1
You don't have PSE valve cut-off with engine rev/car speed on the 997.2 like on the 997.1, so it's not necessary to install remote control on the 997.2. I have verified testing it with a led connected to valve control coil on my 997.2 C4S 2010.
PSE + Sharkwerk Cross-pipe is really a nice mod on the 997.2 !
In 997.1 there was originally a cross pipe (with or without converters) and the common upgrade among the leading companies was to change the modification to x pipe:
Years have passed, and in the original 997.2 it is x pipe (called "center muffler") and now we are "going back" and changing back to cross pipe mode (For example Sharkwerks - with the best sound as I understand it):
*** Note that some companies in 997.2 still chose to replace the original "center muffler" with an improved x pipe. For example Fabspeed / Soul:
All photos for illustration only
GTSpure,
You raise a fantastic question. The reason Porsche chose the original coss pipe design comes down to price savings. Manufacturing X-Pipes in mass quantities and getting the flow as precise as it needs to be, would be astronomically more expensive.
An X-Pipe allows the exhaust gasses to mix and expand, the cross pipe does not get the same effect. Here is our demonstration from a few years ago, Video quality is old, but the physics don't change.
What has started out as a sound/music quality discussion has turned into a comedy channel. However one thing has been noted for everyone to understand is that 997.1 is way different than 997.2. Following that the funny stuff begins with the "technical" explanations. Bernoulli's equation and Venturi's observations were done in 1738 and does not need to be "rediscovered" today. Gas dynamics is a real science but most people missed those classes. Music is art.
Go with what sounds good to you.
You raise a fantastic question. The reason Porsche chose the original coss pipe design comes down to price savings. Manufacturing X-Pipes in mass quantities and getting the flow as precise as it needs to be, would be astronomically more expensive.
An X-Pipe allows the exhaust gasses to mix and expand, the cross pipe does not get the same effect. Here is our demonstration from a few years ago, Video quality is old, but the physics don't change.
Seems to me that in order for the gasses to expand, the velocity of the exhaust gas must slow down within the space. This suggests that the gas mixing is what is slowing it down resulting in the expansion. Isn't that counter-productive when it comes to efficiency of the exhaust system??
OP chiming in . I received the top gear x pipe today. I am astounded by the delivery . 4 days from order placement to delivery on PEI in eastern Canada from uk during the pandemic . That is quite something at any time, i an not exactly at a major hub !
Top gear understands international shipping, ie just use DHL .
Will chime back in when I get it installed to comment on sound improvement if any . I realize the x pipe is unlikely to obtain similar hp performance improvements as sharkwerks due to retaining the ugly 180 degree bend ( equivalent to about 12ft of straight pipe) but I was more after a modest sound improvement. If It needs more the top gear valved solution will likely be step 2 .
Last edited by Airheader911; 02-10-2021 at 12:38 AM.
OP chiming in . I received the top gear x pipe today. I am astounded by the delivery . 4 days from order placement to delivery on PEI in eastern Canada from uk during the pandemic . That is quite something at any time, i an not exactly at a major hub !
Top gear understands international shipping, ie just use DHL .
Will chime back in when I get it installed to commentif on sound improvement if any . I realize the x pipe is unlikely to obtain similar hp performance improvements as sharkwerks due to retaining the ugly 180 degree bend ( equivalent to about 12ft of straight pipe) but I was more after a modest sound improvement. If It needs more the top gear valved solution will likely be step 2 .
Similar experience here... I am also in Canada and shipping was lightening fast. Fit is superb. The only issue is that the supplied bolts are too large in diameter. You will need to buy your own unless they changed this. A bit of improvement in sound over stock but not remarkable. I went the Fister route afterwards which really gives the desired sound, at least for me.
In 997.1 there was originally a cross pipe (with or without converters) and the common upgrade among the leading companies was to change the modification to x pipe:
Still confused. Having owned a 997.1 I never saw anything connecting the left and right exhaust parts like the center muffler does on the 997.2. Look at the 997.1 Tubi conversion sold by Sharkwerks. Two mufflers. One for each side and that's it: https://www.sharkwerks.com/exhaust/p...arrera-TUBX066
So if "there was originally a cross pipe (with or without converters)" what happened to that with a Tubi conversion or any other conversion for that matter. All complete 997.1 after market exhaust systems I've seen have been just like the Tubi. Two side mufflers and nothing else. As opposed to the complete 997.2 systems that all include various versions of cross pipes replacing the center muffler. Here's the Tubi for 997.2 cars. Completely different compared to the 997.1 version: https://www.sharkwerks.com/product?id=4939
Still confused. Having owned a 997.1 I never saw anything connecting the left and right exhaust parts like the center muffler does on the 997.2. Look at the 997.1 Tubi conversion sold by Sharkwerks. Two mufflers. One for each side and that's it: https://www.sharkwerks.com/exhaust/p...arrera-TUBX066
So if "there was originally a cross pipe (with or without converters)" what happened to that with a Tubi conversion or any other conversion for that matter. All complete 997.1 after market exhaust systems I've seen have been just like the Tubi. Two side mufflers and nothing else. As opposed to the complete 997.2 systems that all include various versions of cross pipes replacing the center muffler. Here's the Tubi for 997.2 cars. Completely different compared to the 997.1 version: https://www.sharkwerks.com/product?id=4939
So what's the bottom line? By using Sharkwerks in the Porsche 997.2 is there a separation between right and left exhaust while using FABSPEED there is mixing between right and left exhaust?
BTW, after you install SW with PSE is there more noise of explosions / gurgles while you leave the accelerator pedal? I'm crazy about that sound
Originally Posted by Fabspeed Motorsport
GTSpure,
You raise a fantastic question. The reason Porsche chose the original coss pipe design comes down to price savings. Manufacturing X-Pipes in mass quantities and getting the flow as precise as it needs to be, would be astronomically more expensive.
An X-Pipe allows the exhaust gasses to mix and expand, the cross pipe does not get the same effect. Here is our demonstration from a few years ago, Video quality is old, but the physics don't change.
Thank you John!
Please see my question above. It's definitely interesting
By the way - in the 997 GT3/Rs and 991 the Right bank / exhaust is separated from the Left?
02-05-2021, 01:53 AM
