Exhaust Gurus, X-Pipe vs straight pipe
02-07-2009, 10:44 AM
#1
Nordschleife Master
Thread Starter
Exhaust Gurus, X-Pipe vs straight pipe
I have a cel light indicating, I may need new cats.... with a supercharger, I've always wanted to alleviate some of the bottle neck in my exhaust setup. My setup is Gemballa headers, stock cats and PSE cans... now I have a reason to go to a 200 cell sports cats and doing some research.
The ???, what are the pros and cons of the x-pipe and straight pipe.... both will have 200 cell and OBD2 compliant...
Both setups are about $1500 and both are claiming added power...
In this pics, it doesnt look like they are intersecting on the tight bend, but they are a true X design... meaning, the 2 exhaust are tied together.
The ???, what are the pros and cons of the x-pipe and straight pipe.... both will have 200 cell and OBD2 compliant...
Both setups are about $1500 and both are claiming added power...
In this pics, it doesnt look like they are intersecting on the tight bend, but they are a true X design... meaning, the 2 exhaust are tied together.
02-07-2009, 11:41 AM
#2
Race Car
If they're the same price go X-pipe every time.
The scavenging (sp?) effect that you get from the X will always be a better option than a regular straight pipe.
May I ask who's X-pipe that is? I've been thinking about building my own in this off season without cats completely but it's such a Pain in the rear that I'd rather buy one and bolt it in.
Andy
The scavenging (sp?) effect that you get from the X will always be a better option than a regular straight pipe.
May I ask who's X-pipe that is? I've been thinking about building my own in this off season without cats completely but it's such a Pain in the rear that I'd rather buy one and bolt it in.
Andy
02-07-2009, 11:55 AM
#3
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Red, if they are not intersecting then they are not tied together and it they are not ties together then they are not true X design. If the X pipe in the pic is intersected, then it isn't by much and is probably just enough to try to equalize the pressure. That is the only place they could be intersected.
As you know, the stock exhaust system does not intersect, but "crosses over" so that the exhaust from the right manifold exits the left tip and vise versa. I believe Porsche did that so there would not be any tight "U" bends in the pipe, which may restrict air flow. The set up you posted appears to have tight "U" bends.
There is a thread on the 997 Forum about the 2009 997.2 face lift cars. On the '09 there are 3 mufflers, with the added muffler in the center. It is actually the 1st muffler in the sequence. Below are a couple of pics of the '09 exhaust set up.
1st pic - stock exhaust off the car.
2nd pic - stock exhaust on the car.
3rd pic - X pipe (supposedly intersected) replacing he center muffler.
If the X pipe in the 3rd pic is intersected, then it isn't by much and is probably just enough to try to equalize the pressure. Maybe that is the situation with the pipes in the pic you posted.
I don't know if this helped any, but I am not certain there is a definitive answer.
As you know, the stock exhaust system does not intersect, but "crosses over" so that the exhaust from the right manifold exits the left tip and vise versa. I believe Porsche did that so there would not be any tight "U" bends in the pipe, which may restrict air flow. The set up you posted appears to have tight "U" bends.
There is a thread on the 997 Forum about the 2009 997.2 face lift cars. On the '09 there are 3 mufflers, with the added muffler in the center. It is actually the 1st muffler in the sequence. Below are a couple of pics of the '09 exhaust set up.
1st pic - stock exhaust off the car.
2nd pic - stock exhaust on the car.
3rd pic - X pipe (supposedly intersected) replacing he center muffler.
If the X pipe in the 3rd pic is intersected, then it isn't by much and is probably just enough to try to equalize the pressure. Maybe that is the situation with the pipes in the pic you posted.
I don't know if this helped any, but I am not certain there is a definitive answer.
02-07-2009, 01:05 PM
#4
Parts Specialist
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I agree, cross pipe if you can...I was at the indy shop last night and the tech was putting a custom pipe on a GT3... WOW, that is the way to go.. sounds awesome, looks great and I am told there is less drone then no cross pipe ??
I have not drive/riden in one yet
I have not drive/riden in one yet
02-07-2009, 02:18 PM
#5
Nordschleife Master
Thread Starter
If they're the same price go X-pipe every time.
The scavenging (sp?) effect that you get from the X will always be a better option than a regular straight pipe.
May I ask who's X-pipe that is? I've been thinking about building my own in this off season without cats completely but it's such a Pain in the rear that I'd rather buy one and bolt it in.
Andy
The scavenging (sp?) effect that you get from the X will always be a better option than a regular straight pipe.
May I ask who's X-pipe that is? I've been thinking about building my own in this off season without cats completely but it's such a Pain in the rear that I'd rather buy one and bolt it in.
Andy
The engineers in Stuttgart learned their lessons long ago. You can trace the beneifts of a true dual system back to the 964 and 993. The 964 made 247 hp (250 hp ROW) with a fairly restrictive 2 into 1 exhaust. The 95' 993 increased that number to 272 hp. The major difference in the 95' 993 and the 964 is just the 993 had a true dual exhaust and convertering to a 993 exhaust on a 964 usually nets 20 hp. The 993 got another 13 hp when Porsche changed the intake manifold, heads and cams in 96', but as you can see the exhaust was a much bigger restriction.
Tim... I believe you are correct about equalizing pressure, but also believe that the tight bend are sorta bottlenecking the flow... I guess these are the pros and cons of the X... and yes they are intersecting, but as you can see, not by much.... and I also know about the 997 x-pipe thread, but those were cat (bypassed). This setup is with a 200 cell cat.
was the gt3 an x-pipe design... so your shop is pro-x design?
