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got pics of correct/incorrect pulse wheel

Ever heard of a dual plane manifold? Two separate, and different length, port runners feeding a common intake port.

Also you are forgetting you are moving the injector to the denser and slower air flow. When the ports combine the denser air expands into the secondary airfow. Imagine a swirling venturi effect as the faster air rushes out of the secondary port.

For that matter you are also forgetting the fact a split port injector ONLY feeds the primary port and valve. That is even worse for fuel atomization because you are supply two ports worth of fuel with under half the airflow. The secondary port supplies significantly more then half the airflow at WOT.

Using the 3L manifolds is an option but it requires far more fabrication to get everything to work properly. Some foolish people hack this job and are left with numerous problems. (plugged EGR, so so IAC, mickey mouse linkage, etc) To do this proplery takes more skill than most people on any of the boards have hence the countless horror stories. Also you are left with the underachieveing plastic manifolds. Fine for the low rpm oval cams made for a slushbox but overwise a lost cause compared to the SVT cam's powerband. I bet you are going to mention boost. The lower rpm range torque is a waste on this platform and they do not breathe long enough to be of use for a centrifugal S/C which requires rpm to make power. Well I don't know. How small do they make S/C pullies? I bet you eat the S/C or shaft before you find out.

Also using your logic you should not even use SVT cams because they have different valve timing points for each respective valve. Therefore they will hurt power production.


Let's not forget that if what you were saying had any credibility to it then doing it "this way" would garner very poor performance. MPG, drivability, & WOT performance would all suffer. That fact of the matter is that the results are the exact opposite. (quickest NA car, highest HP car to date, high MPG, stock drivability, etc)
 
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Ever heard of a dual plane manifold? Two separate, and different length, port runners feeding a common intake port.

Also you are forgetting you are moving the injector to the denser and slower air flow. When the ports combine the denser air expands into the secondary airfow. Imagine a swirling venturi effect as the faster air rushes out of the secondary port.

For that matter you are also forgetting the fact a split port injector ONLY
feeds the primary port and valve. That is even worse for fuel atomization because you are supply two ports worth of fuel with under half the airflow. The secondary port supplies significantly more then half the airflow at WOT.

Using the 3L manifolds is an option but it requires far more fabrication to get everything to work properly. Some foolish people hack this job and are left with numerous problems. (plugged EGR, so so IAC, mickey mouse linkage, etc) To do this proplery takes more skill than most people on any of the boards have hence the countless horror stories. Also you are left with the underachieveing plastic manifolds. Fine for the low rpm oval cams made for a slushbox but overwise a lost cause compared to the SVT cam's powerband. I bet you are going to mention boost. The lower rpm range torque is a waste on this platform and they do not breathe long enough to be of use for a centrifugal S/C which requires rpm to make power. Well I don't know. How small do they make S/C pullies? I bet you eat the S/C or shaft before you find out.

Let's not forget that if what you were saying had any credibility to it then doing it "this way" would garner very poor performance. MPG, drivability, & WOT performance would all suffer. That fact of the matter is that the results are the exact opposite. (quickest NA car, highest HP car to date, high MPG, stock drivability, etc)
Nothing against you personally but it sounds like you are harping on someone's ignorant bandwagon. Someone who has been proven wrong time and time again.
Oh well. I'll take real world results any day. Some other folks can never get those from what I've seen and heard. That says more then any thing else could ever do. :shrug:

Nope I haven't forgotten about dual plane manifolds but as far as I know they are used for carburated engines and if they are used with fuel injectors they use throttle body injectors for proper atomization of the fuel!

Just for the record: I am not jumping on anyones bandwagon this is my own personal belief and I have discussed this issue with number of engine builders

And no I was not going to go with the boost comment...

I am well aware of the issue with the split port intakes since I mentioned it in my post and I don't recall saying they were efficient...

I do realize your car is the fastest NA to date but you do have the most mods and tuning at the tip of your finger tips ;) Highest hp I haven't seen a dyno sheet and even if you had one comparing dyno sheets from different dynos would be similar to comparing apples to french fries...Lack of drivability doesn't mean that its more efficient that way either, it could also mean that its just not that messed up :crazy:

And about the use of 3L manifolds, IAC does NOT need to be touched so I don't know how one can screw up there! The TB bracket is fairly simple cut and weld or how ever one pursues to bond 2 pieces of metal together... EGR just ditch is and tune for it...
Fuel rail is the only major issue and if one can't figure out a way to do it properly that person should not be attempting to port cylinder heads!
 
DemonSVT - You removed the secondary Butterflies, Correct?

I am slowly working on my 3l upgrade and that is what I am planning to do. I don't like the idea of the single intake runner dumping into two valves.

Do you have Taurus 24lb injectors, if so what year?

Your site and Warmongers are great sources of information. Thanks
:cool:
 
DemonSVT - You removed the secondary Butterflies, Correct?

I am slowly working on my 3l upgrade and that is what I am planning to do. I don't like the idea of the single intake runner dumping into two valves.

Do you have Taurus 24lb injectors, if so what year?

Your site and Warmongers are great sources of information. Thanks
:cool:

LOL!!!! You don't like the idea of single intake runner dumping into two valves? Elobarate please? What is so wrong about this????
 
On the SVT you have two runners each going to it's own valve. The Oval port heads have an oval runner, that has more volume to supply to both valves.

If you leave the secondaries in when you switch to the Oval port heads you get the situation I mentioned. At low RPM only the long small runner is open. The air rushes out of it into the oval port and then into the chamber. The key to the signal runner is the swirl that caused the flame to spread faster in the chamber. If the swirl happens in the oval port outside the chamber then enters through two valves you have less velocity to create the swirl again - thus the flame spread slower and creates less low end torque.

I saw once how someone welded up the oval port to have two individual runners. It looked really good, but would be time consuming and frusterating.

I think it would be best to just open up both runners all the time. Then at least you are getting some more air in at low RPM ranges, hopefully keeping the torque the 3L had to begin with. Then at high RPM you do not have the secondary butterflies blocking some of the space in both runners.

Also if you are able to make use of Resonate ram tuning in the short runners at high rpm - why couldn't you get some effect from the long runners at low rpm?

*** Disclaimer *** Those are just my thoughts on the issue. I have not done any testing to prove them. If I only had that much time and money.
 
On the SVT you have two runners each going to it's own valve. The Oval port heads have an oval runner, that has more volume to supply to both valves.
And this is bad because??? THE POINT OF THE DUAL RUNNER INTAKE ALONG WITH THE USE OF THE IMRC IS TO BUMP THE LOW END TORQUE ON THE 2.5's

If you leave the secondaries in when you switch to the Oval port heads you get the situation I mentioned. At low RPM only the long small runner is open. The air rushes out of it into the oval port and then into the chamber. The key to the signal runner is the swirl that caused the flame to spread faster in the chamber. If the swirl happens in the oval port outside the chamber then enters through two valves you have less velocity to create the swirl again - thus the flame spread slower and creates less low end torque.
I am confused, when you say oval port are you referring to the ported oval port to accept the dual runner intakes?

I saw once how someone welded up the oval port to have two individual runners. It looked really good, but would be time consuming and frusterating.
Why would anyone waste their time doing this when they can just use the later split port heads and end up with the same thing

I think it would be best to just open up both runners all the time. Then at least you are getting some more air in at low RPM ranges, hopefully keeping the torque the 3L had to begin with. Then at high RPM you do not have the secondary butterflies blocking some of the space in both runners.
You just said "I don't like the idea of the single intake runner dumping into two valves"... So you would rather have 2 unequal, size&length runners meet right before the combustion chamber while the injector is spraying from one side and feed the both valves like that???
 
And this is bad because??? THE POINT OF THE DUAL RUNNER INTAKE ALONG WITH THE USE OF THE IMRC IS TO BUMP THE LOW END TORQUE ON THE 2.5's

I did not say this was bad. You wanted me to explain so I started at the beginning. Both of these systems obviously work well.


I am confused, when you say oval port are you referring to the ported oval port to accept the dual runner intakes?

Sorry, I guess I thought everyone would understand that you would have to port the oval port to make it fit the dual runner system. So, I guess yes I am referring to the ported oval port.

Why would anyone waste their time doing this when they can just use the later split port heads and end up with the same thing

That is what I am saying, but it makes them individual runners like the original 2.5L had.


You just said "I don't like the idea of the single intake runner dumping into two valves"... So you would rather have 2 unequal, size&length runners meet right before the combustion chamber while the injector is spraying from one side and feed the both valves like that???

Yes, that is exactly what I am saying. I will probably shape the LIM a little to have a nicer transition then a flat dump, but from what I have learned about intake manifold design I think that would be better then one dumping into two.

I also think that having the injector on the side is better to allow it to go in through one valve and not hit the divider.

Also then the manifold would be better suited for Forced Induction if I ever get to that point.

If you feel that it is best to use the plastic oval intake manifold that is great, but I like the look of the SVT intake. I also want to get away from the oil issue that caused me to have to install a new engine, and I want the lower compression ratio for future FI.
 
OK I can't take this anymore!!!
Converting oval ports to split ports by porting the way people are doing is just stupid...
Think! The stock split ports have separate primary and secondary ports until the combustion chamber, the primary port is the only port with the injector and the secondary port just delivers extra air at higher rpms...
In the oval ports you have 1 port per cylinder where all the air entering the combustion chamber is mixed properly before it enters the combustion chamber...

Now when you convert the oval port to split port you are feeding 2 unequal length, unequal size runners right before entering combustion chamber and your thinking the fuel is getting mixed properly?!?!!?!?!?!!?!?!?!!!!!
Not only you are killing velocity but why even use a dual runner UIM which is not even meant to be used in this fashion...
If you want to keep the stock look for UIM purposes use the proper heads...



Honestly I think I've explained my view on it ad-nauseum, and no offense to you or anyone with your own ideas but I think the proof is in the pudding.

The IMRC will still work with the oval heads. I believe it is better because the fuel is able to be pulled in through both valves even when the IRMC is closed hence you get a cleaner valve and potentially better mixing, or at least not worse.

The function of the IMRC system is still preserved because the absolute smallest part of the intake runner is right there in the lower intake primaries. This means that with the second intake runner blocked off, the same amount of air is going through the primary runner as it was before when using a split port head.
Just because the destination of that air splits into two valves instead of one doesn't mean it will suddenly suck more or less air through the same size tube. The potential airflow is still the same.
When the secondary port opens then more than twice as much airflow potential is now available. So what is differen't? ONLY the fact that the airflow through the primary runner is now feeding through both valves to the cylinder instead of just one.

So the system preserves the good things of the IMRC system and IMO improves fuel mixing and promotes cleanleness.

EGR IS a big enough deal that I would like it to work. In fact, I made all my systems function as close to original/stock as possible, and with good reason.

The fuel system is a huge reason not to screw with it. The factory designed fuel system undergoes countless hours of testing for reliability and safety not to mention all the actual road data from owners that they gather during warranty repairs. There is no way a home built system can have this kind of "peace of mind".
Would I do it if I needed to? Yes. I have faith in my work, but even with that put aside I have faith in my ability to pay attention to my car, inspect it regularly, walk around it, and in general my awareness to all things mechanical. I have a lot of experience.
But fortunately for me I don't have to choose to do that. The choice lies clearly in the court of doing a simpler modification for converting to split ports and retaining 99% stock components and functionality, and it has produced some of the nicest running and most powerfull cars to date, to include boosted ones.
I dont know of anyone who having gone with the split port conversion has decided that it wasn't that good and went back to oval port.
Also, I have not seen any straight oval port swap set down higher numbers than the split port conversion motors.

To paraphrase what someone else was pointing out:
You measure success by the results.
If the results are different from the expectations, then figure out why or change the way you are looking at it.
 
EGR IS a big enough deal that I would like it to work.

Just want to make sure that you know the only reason for the EGR system is to reduce NOx under certain engine conditions by adding an inert gas to the combustion to reduce temperature.

To me EGR is a big deal also because NOx causes SMOG.:nonono:
 
My concern is not with what happens outside the combustion chamber, it is what happens inside. It is all about the velocity of the air entering the chamber. I think that the velocity will go down with two valves, at low RPM. That is why I do not think that it will have any bad side effects to remove the secondaries.

So, I guess we will see. Hopefully I can take a dyno run once I get this thing running - someday - at the rate I am going.
 
correct me if I am wrong but wouldn't the velocity be greater with only the primary runners supplying air under low RPM just the mass being less?
 
It would be until it openned up into the head where it had access to both valves. Then the air would slow down due to the larger volume. As the air entered the chamber it would have less velocity then it would have had through one valve.

The velocity is what creates the swirl in the cylinder to cause the burn to be a little hotter giving more torque.

But, again that is just book learning - I have not tested anything and I could have forgotten stuff in the last couple years since studying it.
 
Honestly I think I've explained my view on it ad-nauseum, and no offense to you or anyone with your own ideas but I think the proof is in the pudding.

The IMRC will still work with the oval heads. I believe it is better because the fuel is able to be pulled in through both valves even when the IRMC is closed hence you get a cleaner valve and potentially better mixing, or at least not worse.

The function of the IMRC system is still preserved because the absolute smallest part of the intake runner is right there in the lower intake primaries. This means that with the second intake runner blocked off, the same amount of air is going through the primary runner as it was before when using a split port head.
Just because the destination of that air splits into two valves instead of one doesn't mean it will suddenly suck more or less air through the same size tube. The potential airflow is still the same.
When the secondary port opens then more than twice as much airflow potential is now available. So what is differen't? ONLY the fact that the airflow through the primary runner is now feeding through both valves to the cylinder instead of just one.

So the system preserves the good things of the IMRC system and IMO improves fuel mixing and promotes cleanleness.

EGR IS a big enough deal that I would like it to work. In fact, I made all my systems function as close to original/stock as possible, and with good reason.

The fuel system is a huge reason not to screw with it. The factory designed fuel system undergoes countless hours of testing for reliability and safety not to mention all the actual road data from owners that they gather during warranty repairs. There is no way a home built system can have this kind of "peace of mind".
Would I do it if I needed to? Yes. I have faith in my work, but even with that put aside I have faith in my ability to pay attention to my car, inspect it regularly, walk around it, and in general my awareness to all things mechanical. I have a lot of experience.
But fortunately for me I don't have to choose to do that. The choice lies clearly in the court of doing a simpler modification for converting to split ports and retaining 99% stock components and functionality, and it has produced some of the nicest running and most powerfull cars to date, to include boosted ones.
I dont know of anyone who having gone with the split port conversion has decided that it wasn't that good and went back to oval port.
Also, I have not seen any straight oval port swap set down higher numbers than the split port conversion motors.

To paraphrase what someone else was pointing out:
You measure success by the results.
If the results are different from the expectations, then figure out why or change the way you are looking at it.

The IMRC will work no one said it wouldn't but is it really needed? What is the purpose of the IMRC and dual runner intakes??????
So you figure with an oval port converted to split port there is a potentially better mixing? How do you figure its not worse? Have you gone through the countless hours of the testing the factory does?
Your entire idea of how the oval port converted to split port is all fine and dandy but you are really forgetting the lack of separation between the air with different velocity and the enormous port size which just kills the velocity...

I do really think its easier to fabricate a fuel line than to come up with an entirely new head port design don't you think?

What is the big deal about EGR except emissions care to enlighten me? EGR is an emissions control device nothing else, if your so worried about emissions why not keep the precat's too?
 
If the split ports are SPLIT YES
If the oval port is hacked to be split NO!
Yea I was talking about a true split port.

I am gonna have to agree with you on what you say. I went straight 3L for a number of reasons but the big one was that I dont think how a lot of people use JB weld and other methods of modifying the heads is a very smart approach. I dont have the money to have the heads done right (IE machine shop) and I am not going to waste a good motor because the JB weld broke loose.
 
The IMRC will work no one said it wouldn't but is it really needed? What is the purpose of the IMRC and dual runner intakes??????
So you figure with an oval port converted to split port there is a potentially better mixing? How do you figure its not worse? Have you gone through the countless hours of the testing the factory does?
Your entire idea of how the oval port converted to split port is all fine and dandy but you are really forgetting the lack of separation between the air with different velocity and the enormous port size which just kills the velocity...

I do really think its easier to fabricate a fuel line than to come up with an entirely new head port design don't you think?

What is the big deal about EGR except emissions care to enlighten me? EGR is an emissions control device nothing else, if your so worried about emissions why not keep the precat's too?

I read on DemonSVT's website that you need to keep the IMRC installed so that the computer does not go into limp home mode. I guess he did a lot of programming and testing to make his car work well with out it.

The Taurus intake manifold was developed for the Taurus and not for a sporty car. When they make the SHO they put an intake similar to the Contour's on it. Actually that is where the contour intake came from. So, when Ford spent countless hours developing the Taurus Oval port intake system - they were developing a system that would have the characteristics that anyone from a teenager to a grandma would feel comfortable with.

When you want to increase the power in something you have to think outside what might be on the car already and modify it. The plastic intake manifold is non-modifiable you can not even hone it.

Please do some research into Resonate Ram Tuning. Then you might better understand the benefit of the different size runners. There is more to it then seperating the air.

Yes, EGR is just an emission control devise. But, unlike some others it does not get in the way of preformance. It is strickly there to reduce NOx during specific engine cycles to help the car meet the mandated emissions rating. I can not remember the exact details at the moment, so I do not remember the exact cycle.

I would personally rather make an intake then a fuel rail. I'll have to check at work and see what we safety code we give our diesel fuel lines, but due to the explosive properties of gasoline I would think it is even higher.

This has kind of been a fun discussion - eventhough we got a little off topic.
 
I read on DemonSVT's website that you need to keep the IMRC installed so that the computer does not go into limp home mode. I guess he did a lot of programming and testing to make his car work well with out it.

The Taurus intake manifold was developed for the Taurus and not for a sporty car. When they make the SHO they put an intake similar to the Contour's on it. Actually that is where the contour intake came from. So, when Ford spent countless hours developing the Taurus Oval port intake system - they were developing a system that would have the characteristics that anyone from a teenager to a grandma would feel comfortable with.

When you want to increase the power in something you have to think outside what might be on the car already and modify it. The plastic intake manifold is non-modifiable you can not even hone it.

Please do some research into Resonate Ram Tuning. Then you might better understand the benefit of the different size runners. There is more to it then seperating the air.

Yes, EGR is just an emission control devise. But, unlike some others it does not get in the way of preformance. It is strickly there to reduce NOx during specific engine cycles to help the car meet the mandated emissions rating. I can not remember the exact details at the moment, so I do not remember the exact cycle.

I would personally rather make an intake then a fuel rail. I'll have to check at work and see what we safety code we give our diesel fuel lines, but due to the explosive properties of gasoline I would think it is even higher.

This has kind of been a fun discussion - eventhough we got a little off topic.

You make it sound like the Contour is a Ferrari, Contour wasn't designed to be a sports car the last time I checked... :rolleyes:
The discussion here isn't the intake manifolds either its the HEAD PORT DESIGN!!! And there are a number of different metal UIM's available for the 3L if it makes you happier...
Thanks but I am aware of intake resonance and its effects but if you actually understood this then you would also understand that the intake manifold designed for the 2.5 will be different than the one designed for the 3.0...
THE PURPOSE OF A DUAL RUNNER INTAKE WITH IMRC IS TO BOOST LOW RPM TORQ THATS IT THATS ALL THERE IS NO OTHER REASON!!!!!!!!
 
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