Position of X-Pipe important?
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Eurocharged 2004 E500, Eurocharged ECU/TCU 2005 SL600, 2010 Caddy SwaggerWagon
Position of X-Pipe important?
Since there's not a whole lot of E500 exhaust modding going on, I thought I'd pose the question here. I'm having my 2nd cats and resonator removed on Monday. Shop doing it wants to install the x-pipe right where the 2nd cats would be. I've seen most people install the x-pipe where the resonator would've been. Any problems with this setup?
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the position of everything to do with your exhaust is important if you're looking for optimum performance. it's part of the reason many people see a loss of power by just slapping things in/on their exhaust.
not that you're going to see much/any performance out of it but you're likely better off with them where you're shop is wanting to put them instead of way back at the resonator.
not that you're going to see much/any performance out of it but you're likely better off with them where you're shop is wanting to put them instead of way back at the resonator.
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2004 E55
Exhaust tuning is very important, and not very easy to do correctly. I think most of us put the x-pipe where the resonator is out of convenience since we are usually removing the resonator at the same time. That however, does not make it the ideal position.
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2004 E55
Actually it's easy for a fabricator to find the optimum X/H-Pipe location
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I have mine at the resonator but placing them in place of the secondaries is better for the E55ks since that is where we lose more backpressure.
Every setup is different. Honestly, you will not see much if any gain with it on the E500. I would put it at the resonator IF AT ALL. I like the thud thud sound of a V8 at idle though.
Every setup is different. Honestly, you will not see much if any gain with it on the E500. I would put it at the resonator IF AT ALL. I like the thud thud sound of a V8 at idle though.
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2004 E55
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I have mine at the resonator but placing them in place of the secondaries is better for the E55ks since that is where we lose more backpressure.
Every setup is different. Honestly, you will not see much if any gain with it on the E500. I would put it at the resonator IF AT ALL. I like the thud thud sound of a V8 at idle though.
Every setup is different. Honestly, you will not see much if any gain with it on the E500. I would put it at the resonator IF AT ALL. I like the thud thud sound of a V8 at idle though.
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I don't like it that far up because you lose all the characteristics of a dual exhaust. It becomes a single from that point on. That may or may not be good for scavenging, but I hate it for street duals...
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And in all actuality, the x-pipe will only be placed about 18 inches closer to the primary cats then if it was installed in the resonator's location. My question was really asking if there would be any adverse affects with moving closer to the primary cats.
Drugs are bad, Jangy. Bad.
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2004 E55
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Wait, you and your scientific mumbo jumbo is confusing me. After the primary cats, they will join at an x-pipe then break back out into duel plumbing. Then back to the mufflers and out to atmosphere. At no time does it become a single outlet system.
And in all actuality, the x-pipe will only be placed about 18 inches closer to the primary cats then if it was installed in the resonator's location. My question was really asking if there would be any adverse affects with moving closer to the primary cats.
Drugs are bad, Jangy. Bad.
And in all actuality, the x-pipe will only be placed about 18 inches closer to the primary cats then if it was installed in the resonator's location. My question was really asking if there would be any adverse affects with moving closer to the primary cats.
Drugs are bad, Jangy. Bad.
The position of the X-pipe will affect the backpressure and scavenging. As bobgod said, that is a matter of tuning. Your car honestly does not care nearly as much as a forced induction would. Putting the X farther up will make it SOUND smoother. You may like that or you may not. My personal preference for SOUND is to be able to hear both banks as in an old school V8. Low RPMs and a nice thud thud simply can not be duplicated with a V6 or straight anything is all.....
You are over-analyzing...
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Isn't this the OEM setup? Does the resonator not act like a pseudo x-pipe? I've never seen a cross-section of our resonators but at first glance it certainly looks like only 1 chamber in there.
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2004 E55
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See yeah
PS: Check out Kennebell, or vortech for some exhaust theroy 101
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2 into 1 into 2 is not True duals as defined by old school V8s. Nothing scientific there.
The position of the X-pipe will affect the backpressure and scavenging. As bobgod said, that is a matter of tuning. Your car honestly does not care nearly as much as a forced induction would. Putting the X farther up will make it SOUND smoother. You may like that or you may not. My personal preference for SOUND is to be able to hear both banks as in an old school V8. Low RPMs and a nice thud thud simply can not be duplicated with a V6 or straight anything is all.....
You are over-analyzing...
The position of the X-pipe will affect the backpressure and scavenging. As bobgod said, that is a matter of tuning. Your car honestly does not care nearly as much as a forced induction would. Putting the X farther up will make it SOUND smoother. You may like that or you may not. My personal preference for SOUND is to be able to hear both banks as in an old school V8. Low RPMs and a nice thud thud simply can not be duplicated with a V6 or straight anything is all.....
You are over-analyzing...
http://www.youtube.com/watch?v=MG-eBXj0WEs
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2004 E55
Although in theory this is true, once you have a positive pressure wave from the intake coming off its seat, aka supercharger, there is NO scavenging effect. In a nut shell, FI cars like a VERY free flowing exhaust, PERIOD. Prime example, F1 or NHRA, not much of a x pipe or scavenging going on with these boy's engines
See yeah
PS: Check out Kennebell, or vortech for some exhaust theroy 101
See yeah
PS: Check out Kennebell, or vortech for some exhaust theroy 101
The V-8 engines we typically modify for increased output are normally categorized as four-cycle units. Although pretty much the case for a regular street machine, this is far from being the case for a high-performance race engine. If we consider a well-developed race engine, the usual induction, compression, expansion (power stroke) and exhaust cycles have a fifth element added (Fig. 2). With a race cam and a tuned-length exhaust system, negative pressure waves traveling back from the collector will scavenge the combustion chamber during the exhaust/intake valve overlap period (angle 5 in Fig. 2). To understand the extent to which this can increase an engine's ability to breathe, let's consider the cylinder and chamber volumes of a typical high-performance 350 cubic-inch V-8.
Assuming for a moment no flow losses, the piston traveling down the bore will pull in one-eighth of 350 cubic inches. That's 43.75 cubic-inch, or in metric, 717cc. If the compression ratio is say 11:1, the total combustion chamber volume above this 717cc will be 71.7cc. If a negative pressure wave sucks out the residual exhaust gases remaining in the combustion chamber at TDC, then the cylinder, when the piston reached BDC, will contain not just 717 cc but 717 + 71.7 cc = 788.7 cc. The result is that this engine now runs like a 385 cubic-inch motor instead of a 350. That scavenging process is, in effect, a fifth cycle contributing to total output.
But there are more exhaust-derived benefits than just chamber scavenging....
Assuming for a moment no flow losses, the piston traveling down the bore will pull in one-eighth of 350 cubic inches. That's 43.75 cubic-inch, or in metric, 717cc. If the compression ratio is say 11:1, the total combustion chamber volume above this 717cc will be 71.7cc. If a negative pressure wave sucks out the residual exhaust gases remaining in the combustion chamber at TDC, then the cylinder, when the piston reached BDC, will contain not just 717 cc but 717 + 71.7 cc = 788.7 cc. The result is that this engine now runs like a 385 cubic-inch motor instead of a 350. That scavenging process is, in effect, a fifth cycle contributing to total output.
But there are more exhaust-derived benefits than just chamber scavenging....
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Yes, Clayton....the OEM setup has two spots where it crosses. there is a tiny crossover at the primary cats and then the resonator. BUT, keep in mind that MB wants it to be SMOOOOTH....
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You can blame me for the confusion, but X-pipes and their true worthwhile gains have long been a controversy here...
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Hopefully.
The good news is, I'll have pre/post dyno results to confirm.
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2004 E55
Exhaust scavenging is exhaust scavenging, and it is irrespective of naturally aspirated or forced induction engines. Scavenging starts before the headers and is present in our engines, as well as N/A V8's.
Taken from this article: http://www.superchevy.com/technical/...exh/index.html
Taken from this article: http://www.superchevy.com/technical/...exh/index.html
and yes it does work on a supercharged engine, just like it works on a NA motor, we just have less of the effect due to our lowered (Virtually Nil) overlap
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2004 E55
Fair enough. I don't dislike the smooth sound. I'm just looking for a bit more grunt with no loss of HP/torque. It sounds like a secondary cat and resonator delete and inserting an x-pipe, regardless of location, will accomplish this. I really just wanted to confirm that moving the x-pipe closer to the 1st cats, instead of placing it where the resonator used to live, would not cause any loss of performance.
Hopefully.
The good news is, I'll have pre/post dyno results to confirm.
Hopefully.
The good news is, I'll have pre/post dyno results to confirm.
Straight pipe your cat/resonator delete, then apply some spray paint to the hot pipes, where it burns off first is where you locate your X/H pipe
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2004 E55
I understand that scavenging is good for all types and isn't it even so that the X pipe could help non aspirated more, since it does not have the downsides of playing with backpressure?
You can blame me for the confusion, but X-pipes and their true worthwhile gains have long been a controversy here...
You can blame me for the confusion, but X-pipes and their true worthwhile gains have long been a controversy here...
The bigger question is what is a non aspriated motor? Electric?
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If I am not mistaken the best way to determine the location of the "X" is to run straight pipes all the way back, run the car and then take some infared temps of the straight pipes, the point at which it is the hottest is where you cut the pipe and fabricate your "X". This is the way several tuners/shops have done some of my cars that way and if I'mnot mistaken that is how Evosport does theirs too.
