x-pipe and exit in front of rear tires?

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I think that this info I found on another site is as good an explanation as I have seen comparing "H" vs "X" exhaust Crossovers:



"With all this discussion about changing Mufflers and Exhausts I thought I would take a moment to explain why you have a cross over pipe (what we call an H or X pipe!), and the difference in concept between the two popular designs. This might help you decide if you which you want to go with!

The firing order of all production V8s, regardless of make, has one cylinder in each bank that will fire within 90 degrees of crankshaft rotation of another cylinder in the same bank. This occurs twice during completion of the entire firing order. These two cylinders will be exhausting almost simultaneously into the same exhaust manifold system.

Full-length four-tube headers help separate these pulses until the collector is reached. If this is a full race car running "open exhaust", you will notice the collector dumps into a short open pipe at least 2.5 times the size of the header pipes, or the header pipes dump direct without a collector. This is done to avoid the conflict of pressure caused by the timing of the 2 counter firing cylinders, which will create back pressure and degrade torque, horsepower and general performance, especially at higher RPM.

On a full exhaust system, after the header tubes dump into the collectors, the two close firing cylinders are fighting each other for space in the collector and exhaust pipe. The result is reflected pressure waves traveling back up the exhaust system, backpressure, lost power and poor economy.

At the same time two cylinders exhaust in one bank, there is no activity in the opposite bank. The traditional H-pipe equalizer allows some of the excess pressure to bleed over to the 'quiet side' of the exhaust system, resulting in some low and mid-range torque improvements. At high RPMs, however, in traditional exhaust systems, the gases cannot bleed across the H-pipe fast enough to help power significantly. Performance systems with the H pipe design, attempt to over come this by using a shorter cross over pipe which is also slightly larger in diameter as the main exhaust, then would be used in a standard exhaust.

To overcome the power loss of "over loading" the H pipe design, Exhaust manufacturers came up with the X pipe design, which features a tangentially Siamese crossover junction to synchronize exhaust pulses. The X-pipe concept is to split the flow in the crossover junction, so the pressures on both banks will be equal and pulse-free after the crossover, regardless of the rpm. Volumetric efficiency and power are therefore improved at all engine speeds. The negative aspect to the X pipe design is, because of the crisscrossing of the flow stream, harmonic pulsations will develop on some systems at certain RPMs, which will be perceived as a buzzing or humming sound.

A newer concept is a "Channel Pipe", where as two pipes are welded together in parallel with a baffle in between them which allows for mismatched pressures and pulses to cross to the idle side while allowing full, uninterrupted or redirected flow of the exhaust stream through the system.

Also... There is yet another option.... The MAC Prochamber.

It looks like a box, or a muffler where the 2 header leads enter one end and then exit the other in the location of the H or X pipe.

It is essentially a combination of all three basic designs I discussed, incorporating the crossover flow of an X pipe – the open buffer of an H pipe and the passive pulse control of a ported baffle channel pipe. MAC is the ONLY maker to have this design.

Basically it combines the exhaust into a single box, where the 2 inlets extend into the box a few inches to prevent reversion and open dumping exhaust into the box. The outlets are flush with the back of the box and there is a baffle between the sides with ported slots directing the flow of the inlets to cross to the other side. The Box holds backpressure at a steady rate, which eliminates scavenging.

There are many who believe the Prochamber will give increased performance values. Everyone using them will tell you they make a deeper yet quieter tone to the exhaust note.

================================================== =============================

Some of you ask about a Cross Over on a V6.

In the case of the V6, with their “Even Firing Sequence… Having a crossover or not, is very dependent on the size of the exhaust and distance from the engine of the pipes placement. A cross over is not required if the exhaust is “tuned” to the engine. Tuned systems are nearly always without a crossover pipe because the length and diameter of the exhaust is specifically designed to work with your engine at a specified RPM Range to avoid reversion and scavenging.

On a V6 there is no need for a crossover due to the even firing engine. However, it has been proven that in some instances, a crossover pipe will decrease backpressure and allow for a higher flow. If the crossover pipe is too close to the engine, it allows the pulse timing of the opposing cylinders exhaust cycles, to crash into each other – that is to say, the pressure from a right cylinder will still be present in the left pipe when the left cylinder opens to vent. Too far a placement can create a “Pulse Vacuum”, causing diminished pressure on the venting opposing cylinder, causing decrease in torque (Called Scavenging). .

Proper design and placement of the cross over will allow a balance of pressures across the system and therein increase torque, especially at lower RPM.

Also, it has been shown that having a cross over pipe mellows out the raspy “ricer” sound that occurs above 3000rpm. So some people install them just for their “sound” value.

So, the bottom line is, you probably should have a cross over pipe on a V6 exhaust, even though it is not needed. There is minor performance gain and sound gain as well.

================================================== ===================================

NOW - A couple of people ask about the Cross Over on a Motorcycle - They usually only have 2 Cylinders.

It is actually a little more technical but I’ll try to keep it simple.

In the case of 4 stroke motorcycle engines, the reason for a cross over is this...

After a cylindar fires and the piston cycles “up” - exhausts gas vents through the Exhaust valves, along with the remainder of the “explosion”, exiting the cylinder into the exhaust system.

This explosion creates 2 pulse waves… a Sonic Pulse - and a Thermal Pulse.

When the faster Sonic Pulse leaves the exhaust it has created a vacuum in the pipe behind it, which air pressure will enter the pipe to fill the vacuum. This air will collide with the Thermal Pulse and cause it to reverse. The timing of this event causes exhausted gases to be returned to the cylinder while the exhaust valve is still open therein not allowing all the spent gas to escape and also polluting the environment for your next stroke cycle with fresh air/fuel mix.

This “Event” is call Reversion and seriously degrades performance and lifetime of valves and cylinder heads.

The Cylinders fire opposite of each other – or nearly so on a Harley. So when One side is firing, the other side is idle. Having the cross over pipe allows the pulses to dissipate back and forth between the tubes instead of - or before exiting the exhaust and therein greatly diminishing the effects of reversion and so improve performance and engine life.

Yes - you see a lot of bikes with duels and no cross over. These are usually "Tuned Pipes".. meaning their length and size are tuned to work with the S/T Pulse in such a way that reversion can not return to the engine before the exhaust cycle has ended.

================================================== =============================

So you ask - "Which is the BEST one to have?"

I am sorry to say - the answer to that question is purely subjective."






I hope this helped - ( BTW, my own Dart has a "H" crossover and dumps by the Rear axle)


Cheers..!


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Here you go....x pipe and dumped before the tires...sounds great...loud but can be adjusted to be LOUDER! First two pics are rough-in and the last is finished product in high heat powder coat finish.

Mop
 

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http://www.jegs.com/i/PYPES/958/MVV50S/10002/-1?parentProductId=1017706#moreDetails

Here is my solution. They make a none stainless version for much cheaper too.

Thanks. I am interested to see how these sound? I'm looking for a loud deep rumble..lol

Thanks guys for your input thus far...I have decided to run my exhaust on the side like I planned, however, I am not going to use the TTI X-pipe, as they were kinda being douches at the show this weekend, which steered me away from them... so I'm going with another brand X-pipe...What have you guys used? I guess pypes makes a universal one I could fit to the car? Also I see they have a stainless one, which TTI Doesn't offer...

What do you guys think of the bullet style muffler from dyno-max? Are they like super loud? If I don't use the flowmaster 40's I'm looking for something close to that or similar. Borla also makes a bullet style muffler too...yall like those?
 
Here you go....x pipe and dumped before the tires...sounds great...loud but can be adjusted to be LOUDER! First two pics are rough-in and the last is finished product in high heat powder coat finish.

Mop

Wow...that's great! thanks! can I get a list of all the parts you used?? That's the kind of setup im looking for. :) do you have a sound clip? :)
 
Moparman,

thats a sweet setup... I'm with Mopardude318 on this too... My questions is: way couldn't I run that same setup but have the pypes come out at a 90* and exit out the side? This would prevent me from have to be stuck with a limited number for mufflers and use the ones I already have correct?

Jason
 
Go to pypesexhaust.com site Judge for yourself.
I wouldn't slam anything I was selling either. If you like the X use it. It looks really cool and impressive. I really don't care what anyone thinks or says. With a big exhaust on a little motor any thing will be effective. I have a Full exhaust w tail pipes tied in, headers are 2 inch tubes going to 3 1/2 pipes. Stroker resto SB 13-1 with 360-2 Indy cnc ported heads and a 700 lift comp solid roller. I shift it at 8500 . the rev limit is set at 9000. 829 @ 8000 at the crank, Street Driven! It keeps the area behind it clean for 10 feet plus at an idle. the X don't cut it on my motor. Maybe a 3 inch X on a motor that only needs a 2 1/4 exhaust with 1 5/8 - 1 3/4 tubes is fine. If I was selling x pipes I would tell you anything you wanted to here for the sale. I am not selling either and am telling you from my experiance with an X they are useless except for the oh wow factor,Or Look at my exhaust ain't it cool. Nothing on my Duster is dress up. everything you are looking at was to make it durable and for performance. No corners cut and Its not a trailer queen It is a torsion bar leaf spring driver. There is probably more rubber hanging from the car then is mounted on the wheels, and more money in the motor then in my savings and checking combined. I am telling you an H is all you need do not waist your time with an X unless its for appearance or sound.
 
There is always someone who wants proof. If their wife would tell them she is seing someone else they would still need proof.

1st up, of course we want proof.

2nd, Of course we'd want proof. It'll make the divorce go alot faster and easier! Save my pension as well! :toothy10:
 
My dad god rest his soul taught me alot , one thing he lived by is Believe none of what you here and only half of what you see. So proof is only what you experience yourself. and without that you will never know for sure.
 
Theres ALOT of truth in that. But since we're here and do not have alot of money to be changing out exhausts and runnin the track to see if it works or not, dyno treads to see if it works or not, people will be skeptic.

Most of the time, for me, a set up like you recomend is all I do. My rides are street bound and really do not need every last pony yanked to just simply run around and paste a few others at the local light to light or drag strip run. Rare as it is.
 
My dad god rest his soul taught me alot , one thing he lived by is Believe none of what you here and only half of what you see. So proof is only what you experience yourself. and without that you will never know for sure.

So why are we here on these forums again?
 
H-Pipe vs X-Pipe.

Look at page 3.
http://www.boyleworks.com/ta400/psp/exhaust.html

The X-pipe will flow better than the H-pipe because the exhaust does not have to make 90 degree bends.


True...However there may be This to consider ( from the article I quoted above - post # 26 )

"The negative aspect to the X pipe design is, because of the crisscrossing of the flow stream, harmonic pulsations will develop on some systems at certain RPMs, which will be perceived as a buzzing or humming sound."




YMMV and all that....8)




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My dad god rest his soul taught me alot , one thing he lived by is Believe none of what you here and only half of what you see. So proof is only what you experience yourself. and without that you will never know for sure.


If this is true can you explain how members here have noticed power increases when switching? I question this because I see this a lot since it didn’t work for you it isn’t possible that it works for someone else. Maybe this article would help proven dyno results.
http://www.carcraft.com/techarticles/exhaust_system_installation/index.html
 
H-Pipe vs X-Pipe.

Look at page 3.
http://www.boyleworks.com/ta400/psp/exhaust.html

The X-pipe will flow better than the H-pipe because the exhaust does not have to make 90 degree bends.

that article is nice and pretty wellthought out.but i would not bet my life on the findings in it,especialy regarding pipesizes and generalisasion about that you could step down in diameter after the mufflers and after the X-pipe
reason for this is, steping down in diameter on the tailpipes may only work ok on cars with traditional reflection mufflers,i doubt it works as good with absorbation mufflers,reason is that the exhaust pulse has a chance to slowdown inside the big body of the muffler and smoth out from being a short rapid pulse to just a slower moving flow.

with X-pipes you may be able to go down in size after the X but there is more to it, i would NOT do that with a regular X,since this will mean that you will probably end up with a sharp step where tubesize is decreased right after the x where the exhaust gas may have just started gaining velocity alitle after passing thru a section of a bend that was probably cut out alot more than it was suposed to to make the X,now you may wonder why would the factory cut out the bends to much,this is just a theory i have but look at the cheap ones and then look at the more expensive ones and you see the diference,its probably just to gain space for the welder that welds the pipes togheter. proper way to downsize the tubing after the X if its a well made x worth putting the effort towards would be to basicly cut out a slice of it from the rear all the way to the crosover and taper it down over a longer distance.

not sure if there realy is alot of flow thru the H-pipes,i think its basicly natural expansion to relief preasure and that wont disturb flow much if the mainexhaust tubing is just properly sized in the first place but sure i dont think they are perfect or anywhere near perfect for flow




another thing about X-pipes most of them look absolutely horrible on the inside its not uncomon to find big lumps of weld sticking into them,weldingwire,absolutely no deburing before welding and so on.and dont get me started on how i feel about the theoretical flowcharacteristics of those stamped steel ones..


yes its possible to be a person selling X-Pipes and still have some kinds of honor and honesty about them and to tell the truth

everytime i get a question about how they sound i always say what exhaust sound anyone likes is diferent from person to person,but i cant stand the sound of them on my own car but the few x-pipes i have heard in real life that sounds real good are either on mild engines with absorbationmufflers,or on hot engines with a minimum of mufflers behind them like dynomax bullets or similar.

i prefer H-pipes if a balancetube is needed to take down a few decibels and they usualy sounds a litle better,but i dont doubt that a wellmade X-pipe will make alitle more power and i know alot of people like the sound


back ontopic there realy is not alot of space for mufflers with the pipes out infront of the wheels if you want good groundclearance and a good looking system, i think dynomax has some superturbomufflers and magnaflow has mufflers with both inlet and outlet on the front of the mufflerbody wich will alow you to have your mufflers in the correct possition and keep them out of sight
 
back ontopic there realy is not alot of space for mufflers with the pipes out infront of the wheels if you want good groundclearance and a good looking system, i think dynomax has some superturbomufflers and magnaflow has mufflers with both inlet and outlet on the front of the mufflerbody wich will alow you to have your mufflers in the correct possition and keep them out of sight

i couldnt agree more with this. a 90 coming out of th eback of the muffler is definitely not the best way to go. you are going to lose a lot of ground clearance and the pipe coming out square to the side of the car really doesnt look that good. no matter what you choose, the pipe has to pass below the frame rail or frame connector with enough space that it wont contact, the bottom of the moffler is going to be even lower than that. the mufflers with the in and out on the same end would be the best way to go. check out pic of the camaro ssytem on this site http://www.drgas.com/
 
So what X pipe do you recommend me using with side exit exhaust? So as of now I have headers, 3" summit exhaust and magna flows (I can change them to the single side if needed) and polished square tips.
 
Stay away from the X it is proven to produce less ponies then an H Take your fingers and follow the pattern its a no brainer. Actually robs ponies. Why would you want to cause a collision with your exhaust. Run it straight and use the H to equalize the back pressure. The X was a dream that they are still making money on . Looks cool but just think about it. Is it an X or two Y's?

The facts that you are sitting on?
 
X is a magna flow ss
Mufflers are borlas ss
pipe is Kustum made of typical exhaust tubing plain steel
Diverters are Kirk Racing
tips are cut from u pieces of exhaust tubing
Rubber hook hangers.

Comes off with 6 bolts in less than 5 minutes.

I dont have a sound clip...sorry.

Mop
 
hey momo whats the deal with the 2 turndowns on each muffler?
 
Moparman,

thats a sweet setup... I'm with Mopardude318 on this too... My questions is: way couldn't I run that same setup but have the pypes come out at a 90* and exit out the side? This would prevent me from have to be stuck with a limited number for mufflers and use the ones I already have correct?

Jason

You could but if you notice the exit side of the muffler is past the tires.
You would need to do what they did for TA's curve the pipe back towards the front of the car before you turn out in front of the tires.

Mop
 
You could but if you notice the exit side of the muffler is past the tires.
You would need to do what they did for TA's curve the pipe back towards the front of the car before you turn out in front of the tires.

Mop

Do you think with me making that "U" turn in the pipe causes to much restriction?
 
I'm sure there is some restriction but on street cars the loss is probably not enough to notice. Seems like the factory AAR's and TA's ran them that way at the races so must not have been that bad.

If your trying to get every little ounce of power on the street then I would say scrap any mufflers and run straight pipes all the way.....my opinion only.

I think the look and the sound is more important on a street car anyway..... not to many places on the street where you would want to test your 1/4 mile times. ](*,)

Mop
 
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