Attempted to get duals today...

Discussion in '2005 - 2014 Specific V6 Tech' started by echo7, May 5, 2005.

  1. Actually, at the Muffler Shop I go to, they have an X-PIPE which you can buy by itself.. The part is a exhaust pipe X.. They weld it into the existing straight dual, which should only take about 30min..

    What us V6 owners must remember, is that the way our engine is designed, if we do not allow both sides of the manifold, to work together, you must give up the glorious True V8 sound.. Also, I am here to tell you, that the power you guys have now in the car will diminish should you choose a true dual setup.. Meaning staight pipes, that never intersect.. In a V8 engine, this would not be a problem, in regards to sound.. But the V8 would suffer the loss of power at the lower end..

    I am forcasting more low end torque than stock and more high end HP as well, once the X-PIPE is installed..

    I believe, with the 2005 V6, this has been one of the most important discoveries or discussions to date.. By me needing to feed my hunger for more power, I over shot my goal, to the point of lost HP and torque.. Learning from my mistake and sharing it here, has made it all worth it.. Which is why these types of forums are awsome.. Typically, when you make this kind of mistake, and overcome it, the method is kept to yourself.. In this case, all my V6 brothers will never have to suffer from this type of mis-informed calculation based on our particular engine needs and requirements..

    You better believe, once this is straightent out, I am going duck hunting.. LOL!!

    Meaning the poor sucker with a V8, sitting at the light next to me, once the X-PIPE is installed, will have to eat asphalt once I dig my 255's into the pavement!! LOL!!

    What I really love about the V6, is you cant be as careless as when you have the all out muscle V8.. With the V8 stangs, you can make mistakes, an it may not be as apparent unless you make 1/4 mile passes..

    With the V6, all of our upgrades must be well informed.. We dont have enough power to squander.. We need every bit of what Ford gave us, and must work even harder, to find more! It is indeed challenging..

    My goal, at some point in the future, is to take down a 2005 V8.. This will indeed be a very tough task.. How much money it will take to complete the task, I have no idea at this point.. But I am already $350 in.. The X-PIPE, plus installation, will cost me about $100 bucks more..

    My next purchase will be the ECM computer, so I can remove the top speed limit, and maybe re-calibrate while at a stoplight.. LOL!! This is indeed going to be a very fun summer...

    Also, once it is done, I promise to get the car dyno'd with all the relavant information to post..
  2. MSP,

    No 4-stroke engine requires *any* degree of backpressure to operate well, in fact, the less backpressure, the better. What a 4-stroke engine *does* need is the proper exhaust velocity to run well. If your total pipe volume/diameter is too large It will reduce the exhaust velocity to inefficient levels. You have effectively doubled the cross sectional area of your exhaust and (apparently) reduced the flow velocity to detrimental levels. Therefore, I doubt you will see much of an improvement w/ a X-pipe installed. Possibly (?), but you may have to reduce the pipe diameter to regain (or improve) on the stock setup.

    Thanks for posting your results, it’s a good reminder/warning that exhaust tuning is a lot more complicated than just adding bigger/more pipes.

    One last thought … did you retune your computer for the new setup after installing the “dual” setup?

  3. I really thank you for your input.. Been waiting for someone to chime in on this..

    1 question.. You are aware that the biggest change happened because when I removed the 2 into 1 section of the single exhaust, I essentially have a dual setup which is true dual.. You are aware of this? I mean, my pipes from both sides of the block do not intersect at all, like all V6's and V8 Mustangs do...

    I dont have the computer yet.. But please think about my above statement and reply to this before I proceed.. This way we can focus your appreciated response to the area of need...


    Basically, the diameter of the pipes has not changed.. Maybe the volume has doubled.. But, I know it is because of the true dual-non-intersecting situation because the sound of my car has changed considerably at high rpm.. Starting at around 3500.. Below 3500, it sounds like a fire breathing V6.. Not like before where it sounded as good as an 05 Mustang..

    I have talked to the shop, and they have ordered the true X-PIPE today, and it will be in by WED, or THURS..

    The price for part and installation is $80 US.. Taking my total expenditure for my dual exhaust to $430..


    Did you read in full all of the links I posted yet? By this weekend, most likley Saturday night, I will have a new sound upload for you, and also, a report on whether or not the X-PIPE indeed delivers on above stock performance..

    Basically, at this point, I am convinced of the problem and have somewhat solved it NJStangPilot.. However, you sound very knowledgable and I do appreciate you taking the time to make sure I get this right!! So please post whatever you feel needs to be posted my friend.. :nice:

    Also one more thing..

    I have not doubled the cross-sectional section.. My pipes on both sides go straight to the back muffler from the header, without ever intersecting with each other...

    Please post something stating you understand the arrangement, so I know we are on the same page.. Thanks man!
  4. man this is getting confusing, lol, i think i'll wait a bit before going duals. Don't the GT's come with an H pipe though?

  5. I'm not sure echo7... However, dont worry.. I'm the guinea pig on this one.. You dont have to do anything yet.. Let me get mine finished up this week, and if all goes well, I will share the way I did it with you.. Basically, we have the exact same car..

    I have not done any other mods yet.. Not even an airfilter.. My car is bone stock except for the dual exhaust setup.. So it will be easy for you to follow, if the end results should bare fruit.. I am most confident it will..

    My mission, until the work is actually completed will be the placement of the X-PIPE.. I know the articles I posted suggested using spray paint.. This is most likley how I will do it.. My fear is, what if the paint does not burn away, but burns in? LOL!!

    So I have been crawling under the car, and looking trying to identify the hottest point on the original single exhaust side.. I cant see it so far.. Looking at the picture I posted of the X-PIPE, it indeed is towards the forward middle section of the car.. This is of course due to the Long tube headers..

    We have shorty headers... Any ways, this is where my mind is.. This bugs me because, what if I select a spot thats produces power which is slightly better than stock.. When really, if moved forward or back a few inches, I could have made 10-15 more HP above that, which would be a total of 40 to 50HP above stock..

    These are my thoughts.. I hope more people will respond to these burning questions more frequently.. Maybe I should take these questions to the V8 side.. Maybe they would have more readily available answeres....??


    I am using 40 to 50HP as a hypethetical.. Dont take it literally until I post a dyno test..
  6. MSP,

    If I understand your posts correctly, you have a true dual-exhaust setup. That is, the left bank of 3 cylinders dump into the exhaust header, then through a CAT, then through a long length of 2.5” tubing and finally through a muffler/tailpipe. The right bank of 3 cylinders feeds through a similar arrangement and both sides (left/right) are independent assemblies (i.e. they never connect/touch).

    The reason I said that the cross sectional area has doubled in this arrangement is that you now have 2.0 liters exhaust volume flowing through 2.5” diameter tubing (per unit time), rather than the original full 4.0 liters flowing through 2.5” tubing. Since the original configuration employed a collector and single pipe, the full 4.0 liters of exhaust was essentially limited to a 2.5” max diameter (restriction point) at, and past, the point where the Y was located. This situation is similar to if you had installed a 3.5” diameter single-pipe exhaust arrangement.

    Exhaust systems are usually carefully designed so that the cylinder firing/exhaust sequence, the exhaust header primary length, the collector location and pipe diameter are optimized to produce the lowest possible backpressure while maintaining sufficient velocity for exhaust scavenging. Scavenging means that an exhaust pulse exiting from one cylinder flows past a “connection” point with another cylinder which creates a vacuum in another primary (the section of tube connected to the head) that draws burned gasses out of the other cylinder.

    If you make a small hole in the middle of a straw and blow through the straw while holding a cigarette close to the hole, you will notice the smoke being drawn into the hole as you blow through the straw. This is the effect exhaust velocity has on producing a vacuum in other cylinders to aid removal of unburned gasses.

    Since the installation of the X pipe seems fairly inexpensive, you might as well try it to see if the performance/sound improves much. Note, however, that larger/wider exhaust setups typically produce more top-end power with some loss of low-end power/torque. Since HP = torque x rpms, gaining torque at high rpms will give more peak power than a torque gain at low rpms. You just have to drive the car at higher rpms to utilize the power increase. Course, this burns more gas … but there is always a compromise involved with tuning.

    I will try to address this issue more later. I have to get back to work, but I wanted to send a quick reply to you since I can understand this must be frustrating for you.

  7. That was an elloquent response NJStangPilot!! Far better than I ever thought I could encounter.. I am listening, so when you have time, feel free to educate us on the subject.. Based on your technique, I would say you are either an instructor, or a manager of a shop.. ?? LOL! If I am lucky, you work for Ford Motor Company! LOL!!

    Anyways, yes the X-PIPE comes in tomorrow.. Most likley to be installed on Saturday.. I pretty much only drive my car on the weekends, which is why it is destined to be a total project car with very low miles maintained.. I'll get back to my youth, and play on the weekends with modifications..

    I am really anxious to solve this situation though.. Lets keep in mind, that for most going dual wont be as complicated.. They could just use the "Y" section from their single exhaust and have plenty of power, and an awsome sound..

    So I am saying this so guys dont get confused at my path.. I am trying to setup an alternative mod which will give more gains. It looks like only about $100 bucks more.. Basically, using the existing Y will be the quickest way to success in regards to going dual.. But if I achieve my goal, at least there is another alternative for us..

    I am glad we were able to recruit someone like NJstangpilot, he should keep us on the right track for the time being.. LOL!

    My next thoughts moved towards adding the headers next... I would like to have this project complete and bare fruit, before adding anything else..

    It is essential that I get this Dyno'd to show realtime numbers against a stock setup, so expect to see this..
  8. how would you use the existing Y pipe to go duals?
  9. You would use another Y..

    So from the headers, the Y would be 2 into 1..

    To the mufflers, it would start from a Y reversed going 1 into 2..

    The 2 Y's would meet on the single side..
  10. Excellent information :nice:
  11. MSP,

    Let us know how the X-pipe installation proceeds and the apparent effect on the performance. I think it maybe worthwhile to try this since you have already installed the 2-pipe setup. There is a possibility that the reason you lost power is due to the firing sequence of each bank of cylinders. Basically, a well designed exhaust will have the pressure pulse from one cylinder passing the connection point with another primary just before the exhaust valve opens. The gas movement past this point will generate a vacuum in the other header primary, assisting removal of burned gasses from the cylinder. The firing sequence of the left bank of cylinders (plus the “non-tuned” [i.e unequal] primary lengths of the stock manifold) may not allow the exhaust pulse sequence to coincide with the exhaust stroke of another cylinder unless all 6 cylinders are connected at some point.

    A couple notes to consider:

    1) I suspect that the optimal position for the X-pipe would be where the original Y-pipe was installed. The engineers probably positioned the Y connection at this point to coordinate the pulses with respect to the average pulse flow and exhaust stroke sequence.

    2) I would use an X-pipe designed for the same size tubing you’ve installed. If you use a X-pipe with the same cross sectional area as the original Y-pipe, you MAY(?) be creating a restriction point which basically obviates the benefit of the twin pipe setup. (a chain is as strong as its weakest link, so to speak). I'm not absolutely sure of this but it seems to make sense.

    3) I would contact a respected company like Magnaflow and describe the mods you made and ask if they have any components which may solve your problem. Ask them as if you want to buy parts from THEM to solve the problem. You may get some professional advice on the nature and cause of your problem. They will probably tell you to scrap everything and buy one of their systems, but tell them this is not an option (i.e. you have spent too much already and will go back to the original setup if they can’t help).

    Good luck and keep us posted. Thanks for sharing your results.
  12. My friends!! Fruit has fallen from the tree.. I just got in.. I will elaborate more later.. But the sound is unbelievable at low and high RPM.. The torque has risen maybe about 1000 rpm above stock.. Meaning the nice kick is there.. But amazingly, the car gets a quick jolt of power @ around 4800 to 5000 RPM.. I mean, when you punch it, once it gets to this space in the rpm range, the car will whiplash your head back.. I have no idea why this is...

    Does anyone know what could be happening? I will say, the car never got to 100MPH so fast before.. It seems alot smoother also.. Meaning the rev up is alot smoother than before.. Thus far, I must recommend everyone from V6 owners, to GT owners install the X-PIPE...

    Guys I am completely amazed at the whiplash effect.. I cant think of how the car could be overcome with more power so quickly while already in a hard pull..

    :nice: :D

    Also, the RPM's rev up alot quicker than before..
  13. Now the question is if you installed it one inch more forward, or one inch more back, would it have been better, lol. So where did you end up putting it?
  14. *chanting* sound clip sound clip
  15. Here you go guys.. Some preliminary pics..

    I will see about the sound file tomorrow sometime.. Also, need to get it Dyno'd sometime nextweek, if I can find time to scoot over there..



    These shots have really bad lighting... You deserve better.. I'll post more pics, dont worry..

  16. This is a very interesting scenario.. You are right. I actually have mine installed right at the bend in from the cats.. So, the cats connect to the headers.. At the end of the cats is a small piece of pipe on both sides, which bends inward towards the center of the car.. This is the closest point at which the X-PIPE can go...

    Remember I mentioned the peak torque curve is slightly higher in the RPM range.. Roughly around 1000RPM higher..

    So, it is possible, our calibrations could mean, the further out away from the first curve in the pipes may lower the torque curve...????

    Or is it possible, that I have optimized on the Peak HP from the location I have chosen...????

    I think this is the case.. I feel this way, because it is not just a small jolt while at the upper RPM range while at 80 MPH in 3rd gear.. It is a significant jolt.. Normally, the acceleration from 80 to 100MPH is slightly brisk.. But in my current arrangement, when at 80MPH in 3rd gear, once the jolt happens, 100MPH is only a blink of the eye! Seriously.. I mean in this situation, I can feel a hard smooth pull upto 100MPH, which is all I have had room for thus far..

    One more important note... This is with the gas pedal not floored at all.. I have tested the jolt out no less than 6 times.. Its a real jolt.. One test I did, was to see if I could pull harder once the jolt takes place, being aware of more gas pedal to apply.. Well there is a consistant pull.. I have not yet floored it while in 3rd climbing towards 100MPH.. The cars front end seems to get alittle lighter, and I start to run out of room on the freeway...

    NJStangPilot, whats your theory on whats taking place? This is an important topic in regards to this jolt.. Hopefully someone can maybe shed some light on the subject.. Could it be a case of the cars computer making a change to the timing based on the xpipes ability to more efficiently scavenge at the RPM range of 4500 to 5500?

    I also want to add, the the car will easily hit the 7000RPM mark if I let it wind up.. I am not sure if there is a limiter set in that range, but based on my brief test, the RPM scaling is really smooth now.. It seems as if the engine is not starving once to that level.. There is hardley any noticable vibration while between the range of 5500 and 6000RPM... This was not the case before.. Before, you could tell you were getting close to the redline...
  17. NJstangpilot

    This paragraph of knowledge you shared with me, seems to be the case here...

    Since the installation of the X pipe seems fairly inexpensive, you might as well try it to see if the performance/sound improves much. Note, however, that larger/wider exhaust setups typically produce more top-end power with some loss of low-end power/torque. Since HP = torque x rpms, gaining torque at high rpms will give more peak power than a torque gain at low rpms. You just have to drive the car at higher rpms to utilize the power increase. Course, this burns more gas … but there is always a compromise involved with tuning.

    Although, luckily, I still have some pretty good low end torque, but it appears the best gain did happen at the upper range of the RPM range..

    Meaning, although the lower end is still quite significant, the upper range now produces a noticable boost while accelerating at an already considerable pace.. The jolt...

    Also, while at the muffler shop today, other customers request the owner to order more X-PIPES for their cars.. One guy had a Dodge truck with the HEMI engine.. Another had a 1993 SS Z28 Camero.. LOL!! They were so impressed with the new sound of my Mustang when it was finished, they wanted to give it a try..

    Also, the owner of the shop said he didnt know the XPIPE was able to produce that type of sound...
  18. Im dyin over here lol, im going to turn my computer off until tomorrow night :)
  19. An earlier post of someone said that the ideal placement of the xpipe would be at the location of the original Y, which is like 3 ft from where you put it. I wonder if it really would give you the lower end torque versus your higher. Maybe i should put my x at the Y and see what i get, and we should know from those two, which is better.
  20. Also, what pipe size are you using, stock size whole way?