Manually Opening the Secondaries

[01blkcat]

Is there a way we could "short" the IMRC into thinking the secondaries need to be open at any certain time? I'm think more along the lines of a switch in the cockpit that can be flipped in order to keep the secondaries open, and can be turned back off to keep the imrc to make it's own adjustments.

I'm aware that is was discussed in a couple of other threads, but thought I'd open it up to suggestions in a separate thread.

EDIT: I also know there is a how-to on wiring a physical pressure switch to the secondaries themselves, to light when the switch is triggered. Is there a way to simply splice/tap an IMRC wire to do the same thing? I really don't want to disassemble the manifolds right now to get a light :)

[RodneyBur]

That sounds like a really good idea.

[FastCougar]

That will require a circuit to be built and plugged in "inline" prior to the factory pigtail on the IMRC. Great idea and very ambitious ... who is up to the task of making it though? Any electrical engineers here???

[FastCougar]

You could always rig some fishing line to the IMRC TB cam and drill a very small hole in the firewall to run it to the cabin :rofl:

[01blkcat]

Originally posted by: FastCougar
That will require a circuit to be built and plugged in "inline" prior to the factory pigtail on the IMRC. Great idea and very ambitious ... who is up to the task of making it though? Any electrical engineers here???

I'm an electrical engineer :biggrin:

[RodneyBur]

Originally posted by: 01blkcat

Originally posted by: FastCougar
That will require a circuit to be built and plugged in "inline" prior to the factory pigtail on the IMRC. Great idea and very ambitious ... who is up to the task of making it though? Any electrical engineers here???

I'm an electrical engineer :biggrin:

Quit your day job so you can figure this out and become rich from savy marketing and sales techniques.

[B3NN3TT]

Originally posted by: FastCougar
You could always rig some fishing line to the IMRC TB cam and drill a very small hole in the firewall to run it to the cabin :rofl:


HA HA! Southern Ohio technology! Makes me miss home...

:rofl:

[Fett]

Well, you could do this two different ways.

1) Cut the lead cable going to the inlet runners, connect it to the throttle cable where it meets the TB. This would allow you to control the runners with the throttle.

2) The motor inside the IMRC is a simple two wire, two way motor, not unlike the ones in RC cars. A simple 9 volt battery will opperate it. You could run a three way switch to it, and use the switch to control the runners. The only down fall of doing it with a switch, is you would have to flip the switch to close them as well. But during racing type situations, you would only need to flick it open and leave it open.

[01blkcat]

Originally posted by: Fett
Well, you could do this two different ways.

1) Cut the lead cable going to the inlet runners, connect it to the throttle cable where it meets the TB. This would allow you to control the runners with the throttle.

2) The motor inside the IMRC is a simple two wire, two way motor, not unlike the ones in RC cars. A simple 9 volt battery will opperate it. You could run a three way switch to it, and use the switch to control the runners. The only down fall of doing it with a switch, is you would have to flip the switch to close them as well. But during racing type situations, you would only need to flick it open and leave it open.

Ok then --

1. Where do I this IMRC box/motor on my 01 ATX, and

2. Will this setup allow for the switch to be in a position that would allow the ECU to control the IMRC to open/close the secondaries, or would I be completely in control?

[Fett]

1) The IMRC is located under the water pump shield. (plastic cover that says DURATEC 2.5). You will see a coated lead cable running to the left (your right), and under the air inlet tube (accordian tube). If you cut that cable, you will be able to connect it to the throttle cable. The cable is just like your throttle cable, just like a bike brake cable.

2) You would be in complete control, you would power the motor either way (open/close) with the flick of a switch.

I have seen number one done, and I plan on doing it to my car when I get the chance. We have done it on a number of Sables. I made the second one with a spare IMRC, but I never tested it IN the car. I removed the mother board from inside the IMRC, located a bettery in there, and connected a switch, and tested it on a bench. I didn't go the next step because I didn't feel like running wires through the car to reverse the power and what not.

[01blkcat]

Hmmm...

I like the second idea, but I still want to be able to set the IMRC to run automatically, when I don't want to override it. Sort of like a relay that would only interrupt it should I flip the switch. I'm thinking I could probably go pick up a spare one and play with it, but right now no junkyards in my area have them, so that's not going to be easy.

I basically want a bypass, so that I can kick the secondaries open whenever I want, but when I flip the switch, the IMRC returns to doing it's job of controlling them.

Would I also be able to use the area under the cover to rig up a switch to control an LED inside the car? I don't really want to dismantle the manifolds... is there enough play on that tensioner cable that I could mount a pressure switch somewhere in that area?

[BrantlyJ]

could someone explain what this is all about?? what are seondaries, what will it do to keep them open all the time, etc....

Brant

[PuckPuck]

there are a few wires going into the IMRC box.... I beleive 2 of them are grounds, one of them is a lead, and the other is a return signal... when the PCM sends the open signal to the IMRC it first sends a strong signal to open the motor then a weaker signal to keep it open.... it also expects a return signal, if it does not get this return signal the end result is a CEL.....

BrantlyJ - Look at your engine... the top thing is called your upper intake manifold... see all thoses aluminum runners... you have 12 of them in all... 2 for each cylinder... notice how half of them are long and the other short... theses 12 runners go straight down into your lower intake manifold where the secondaries are located... the long ones are always open, however the short ones are not... when certain engine conditions are met the IMRC (Intake Manifold Runner Controller) opens up a set of butterfly valves (secondaries) to allow air to pass through the 6 shorter runners as well as the longer ones... end result is more HP.... there is more discussion as to why the long vs short runners but this should be enough info to swallow for now

[01blkcat]

PuckPuck - So I would basically have to create a circuit that not only takes a voltage in and through, but would have to create a return voltage in order to keep the ECU happy... damn... that's a lot harder than I thought :(

Would I still be able to simple rig up a pressure switch to the tensioner under the engine cover to set up a pilot light in the cockpit?

[BrantlyJ]

Thanks PuckPuck. kinda has the same theroy of a 4-barrel carb then... kinda thought that was the case. very interesting. Why would you want to have light to tell you when it opens though?? just for novelty?? Personally I think I can tell by the sound of the engine. The tone from the intake changes....

Brant

[GrandMasterKhan]

i was wondering if hooking the Secondaries up to the throttle would have any benefit? maybe down low? and of course you would Never have to worry about them not opening...would doing so throw a CEL?

btw i have my old IMRC box. (i replaced it when it stopped working properly...i can give it to you if you want it for testing...PM me)

[DemonSVT]

Originally posted by: FastCougar
That will require a circuit to be built and plugged in "inline" prior to the factory pigtail on the IMRC. Great idea and very ambitious ... who is up to the task of making it though? Any electrical engineers here???

Yes it can & has been done.

Like FC says it is Not as easy as just rigging up a switch. It's much more involved than just adding or switching one power signal.

[DemonSVT]

Originally posted by: Fett
Well, you could do this two different ways.

1) Cut the lead cable going to the inlet runners, connect it to the throttle cable where it meets the TB. This would allow you to control the runners with the throttle.

2) The motor inside the IMRC is a simple two wire, two way motor, not unlike the ones in RC cars. A simple 9 volt battery will opperate it. You could run a three way switch to it, and use the switch to control the runners. The only down fall of doing it with a switch, is you would have to flip the switch to close them as well. But during racing type situations, you would only need to flick it open and leave it open.

1. Nope. The IMRC box would wind up the "cut" cable and trip a CEL for P1518 - IMRC stuck open. Can't remove or disconnect the box or the car throws a hard CEL and goes to limp mode.

2. Possible. However the 9V battery would drain in a hurry! The electrical motor runs wide open and has to stay energized to hold them open to. Also it's a 12vdc motor. Running off of 9vdc and less amperage would make it very slow and not have nearly the same holding power. Most likely see high rpm flutter of the butterflies too.
CEL is possible since no signal from the PCM wire would be sent back to the PCM. (PCM uses a pass through wire to trigger the IMRC and then let the PCM know it should be triggered) It's tripped by the same switch that signals the IMRC is open. This wires is the other that runs back to the PCM.

[DemonSVT]

Oh yeah.

Hooking the Secondaries to the throttle would negate the whole reason they are there. Might as well just pull them and get the mid to high rpm benefits as well.

It easily boils down to...

If you have secondaries. Leave them alone. Get a chip that opens them a little earlier and be happy.

If you don't have them. You HAVE TO find a way to get the PCM to think they open earlier and get the added timing & fuel ramp up without the CEL - P1518.

This would take a custom chip or a multi-relay circuit with an RPM switch.

[01blkcat]

Originally posted by: DemonSVT

Originally posted by: FastCougar
That will require a circuit to be built and plugged in "inline" prior to the factory pigtail on the IMRC. Great idea and very ambitious ... who is up to the task of making it though? Any electrical engineers here???

Yes it can & has been done.

Like FC says it is Not as easy as just rigging up a switch. It's much more involved than just adding or switching one power signal.


I'm not worried about difficulty. You've said that it has been done... what are the prerequisities to getting this to work? I'll build a circuit, doesn't matter to me... just need some ideas on what it needs to be comprised of, as well as placement.

[PuckPuck]

well this is what i can gather...

the circuit would need to sit between the ECU and IMRC box. The circuit would do nothing until you flip the switch inside the cabin, at this point it would open up secondaries by sending the proper signals to IMRC box.... however it must also tell ECU secondaries are open so you get the full timing advance, however the ECU might flip out because the secondaires should not be open and end up throwing a CEL....

best option, would be get a chip that just opens them earlier.....


HOWEVER creating a circuit that would plug in to the pig tail for IMRC which would return proper signals when told to open would be AWESOME and i would buy one right away. Reason is many people opt to completely remove secondaries however in doing so we end up throwing a CEL and lose the timing advances.... a black box circuit would be great because then the ECU would think everything is operating normally

[B3NN3TT]

I'm far from electrically inclined, nut the descriptions here sound a lot like the circuit built for MIL eliminators. Maybe that concept, modified to the application...

Or maybe I'm WAAAAAY off base...:stupid:

[MaStaMooN]

Like Puck Says, make a box that clips onto the pigtail from the ECU that goes into the IMRC that will act as a psuedo IMRC circuit and you got some cash comming your way!! Got a secondaries delete lower manifold in my garage that im dying to try!

[PuckPuck]

Originally posted by: MaStaMooN
Like Puck Says, make a box that clips onto the pigtail from the ECU that goes into the IMRC that will act as a psuedo IMRC circuit and you got some cash comming your way!! Got a secondaries delete lower manifold in my garage that im dying to try!


you can be second in line... i asked first :)

[MaStaMooN]

Id want to make sure it works well first anywho! ;) :biggrin:

[01blkcat]

Ok then...

Anyone got an old IMRC box that isn't any good anymore, or has a crap one sitting around? I'd like to look at one before I start tinkering with a good one :)

Edit: I know it was said above about a chip, I've had the WeaponR piggyback ECU since I bought the car, and it still doesn't open the secondaries early enough for me. I just want to make a clip that would allow me to manually flip them on, and return the system to normal when I don't need them open all the time.

[Fett]

1. Nope. The IMRC box would wind up the "cut" cable and trip a CEL for P1518 - IMRC stuck open. Can't remove or disconnect the box or the car throws a hard CEL and goes to limp mode.

Limp mode? More information please. It would throw a CEL, yea because there would be no attention bringing the motor back to rest, I agree. But it will and does work, we have done it to quite a few cars....and actually, none of them threw a CEL, at least none of the Sables did. It also does not defeat the purpose of the IMRC by doing this. The IMRC essentially does the same thing as "vtec", it allows for more air intake when you want it. It gives us more tq in low RPMs, and a better top end under "aggressive" conditions (for lack of a better term). Now depending on why you would want to screw with the IMRC in the first place, this would work. The IMRCs have a HUGE failure rate, those things die all the time, and are not covered under extended warranty. So instead of dropping a new IMRC in every six months or so, this is a very viable solution.

2. Possible. However the 9V battery would drain in a hurry! The electrical motor runs wide open and has to stay energized to hold them open to. Also it's a 12vdc motor. Running off of 9vdc and less amperage would make it very slow and not have nearly the same holding power. Most likely see high rpm flutter of the butterflies too.
CEL is possible since no signal from the PCM wire would be sent back to the PCM. (PCM uses a pass through wire to trigger the IMRC and then let the PCM know it should be triggered) It's tripped by the same switch that signals the IMRC is open. This wires is the other that runs back to the PCM.[/quote]

A 9volt battery "WILL" make it work...I personally would use the car battery, which will also work just fine. A cap might be needed, but you can power it off the battery. The PCM does not actually know if the runners are open, the only way it would know is when the cable triggers a "stop" point in the IMRC. The cable lead on the motor itself has a lop sided rim on it, when the motor opens the runners, the high side of the rim touches a simple metal to metal "kill switch". This switch cuts the forewarned power to the motor and signals the PCM that it is open. By doing it manually WITH the motor, this signal would still be sent....you could actually use the kill switch and just power it open and let the tension pull them closed...just like it does now. It would suck to manually open them every time, but it again...would work just fine.

I do agree that messing with the IMRC is really pointless, you should just leave it alone. However, I also understand the frustration of having to replace the IMRC a few times a year. I just replace mine...so far four times, but I get it at pretty much Ford cost...so it doesn't bother me. :)

[DemonSVT]

Fett - You are incorrect here.

There are 2 signals to the PCM from the IMRC.

One is a passthrough that originates at the PCM, goes through IMRC and then back to the PCM to let the PCM know the IMRC is actually suppose to be open.

The other is just a signal telling the PCM the IMRC is open. It is powered up when the switch is tripped at full motor travel. It ALWAYS has power. If the switch stays tripped it will continue to send the signal even though the IMRC/IMRC motor is not powered up.

Manually tripping the IMRC by giving it power would only trip the switch inside the IMRC that tells the PCM it is open. Not let the PCM now it is suppose to be open.
You may have been preventing a CEL because the engine runs long enough after the fact to clear the internal CEL. (Yes a CEL can be stored and the light never comes on!)
However you will not get the timing advance & fuel ramp up that either the CEL (P1518) or proper signal will give you.
Yes I tried just a switch...

9vdc will not properly operate the IMRC. Heck the motor has a hard enough time staying open as is (high rpm flutter is a known problem due to heat, bad connections, and/or weak IMRCs)

Afterwards I did think about the fact you may have meant you were using the battery as a trigger to open the IMRC. (instead of a relay & switch which is the correct way) Thus letting the IMRC still draw it's power from the main power cord.
This is NOT a good idea as you have to match the PCM's signal voltage & amperage or risk damaging it! (since that signal is sent back to the PCM)


...and YES...

Tying the secondaries to the throttle would be pointless. Either use them for the higher low rpm velocity (which I strongly recommend!) or ditch them all together.

"Half assing" them in this manor negates any of the low rpm benefits (They are open! Hence no benefits! It's as simple as that!) and does not gain you any mid to high rpm benefits of removing them. Part throttle above the IMRC point will also be weaker!
1. Also you would not get any timing & fuel ramp up this way.
2. You would still need to control the IMRC point.
3. You would still need to fool the IMRC in some way.


The IMRC CAN NOT be removed or disconnected. The PCM will go to limp mode! I forget the exact CEL, but it's flatline timing & no fuel. It even OVERRIDES a chip!!!
Yes I have tested it long ago. (in the days of Yore ;) :biggrin: )

[Fett]

I see and understand your point, but the ideas will still work. Maybe I should have said work...."better than having a dead IMRC", which is really my only point.

If your IMRC is dead and your runners are not opening, then either of the above suggestions would work in that case. A shade-tree mechanic fix of the runners is better than not having them open at all. However, simply putting a new IMRC in is the best solution.

As far as trying to find a way to make a good IMRC "better" for performance, then yea neither of the ideas are the way to go...you would want to find a way to program the PCM.

We are looking at it from two different points of view, you are looking to modify, I am looking at it as a way to "fix" a broken IMRC.

[DemonSVT]

Originally posted by: Fett
I see and understand your point, but the ideas will still work. Maybe I should have said work...."better than having a dead IMRC", which is really my only point.

If your IMRC is dead and your runners are not opening, then either of the above suggestions would work in that case. A shade-tree mechanic fix of the runners is better than not having them open at all. However, simply putting a new IMRC in is the best solution.

We are looking at it from two different points of view, you are looking to modify, I am looking at it as a way to "fix" a broken IMRC.

If your IMRC is broken. Your best option is pinning them open and running with the P1518 CEL. Until you can replace the IMRC of course.

This is a soft code and it also will ramp up the timing & fuel at 2500rpm since the PCM see's the IMRC as open. (IMRC adders)

[Frank]

All this work for minimal gains...

You don't want the secondaries opening any earlier than they do... it has been shown time and time again on the dyno that 3400RPM is the RPM at which the car produces more torque with the secondaries open than closed. The reason the car is gutless below 3000RPM is not because the secondaries are closed - it's because you have a tiny high-revving 2.5L motor trying to move a 3000lb car... opening the secondaries earlier will only make the situation worse, not better.

I don't mean to sound cynical, but you guys would be better served to use your creative energies on a project that will yield real results...

[CougarDemon]

Originally posted by: Frank
All this work for minimal gains...

You don't want the secondaries opening any earlier than they do... it has been shown time and time again on the dyno that 3400RPM is the RPM at which the car produces more torque with the secondaries open than closed. The reason the car is gutless below 3000RPM is not because the secondaries are closed - it's because you have a tiny high-revving 2.5L motor trying to move a 3000lb car... opening the secondaries earlier will only make the situation worse, not better.

I don't mean to sound cynical, but you guys would be better served to use your creative energies on a project that will yield real results...


yea like an electric turbo...:cover:


seriously though how would it make it worse? not doubting you but the way i'm looking at it is if the secondaries are open its that much more in trying to move your car so instead of all the load being when the secondaries are closed it will disperse more evenly and less with the secondaries open. 'm prolly was wrong but i'm just trying to learn. i always enjoy reading the performance discussions and learning things.

[DemonSVT]

Originally posted by: CougarDemon
seriously though how would it make it worse? not doubting you but the way i'm looking at it is if the secondaries are open its that much more in trying to move your car so instead of all the load being when the secondaries are closed it will disperse more evenly and less with the secondaries open.
Flow dynamics!

Long runner, high velocity air promotes better cylinder filling & fuel atomization at low rpms. Therefore considerably more TQ and a little more HP.
Hence the entire reason why the dual runner intake was designed.

When the engine is using both intake ports it is splitting the incoming air into 2 separate parts and thus effectively halves the air's velocity. (actually a 30mm port + a 32mm Port (DH UIM) would be more than double but it's a close estimation)
While this is not a problem at higher rpms (as the engine is sucking in much greater volumes of air through the 2 ports) it is such at lower rpms.

[GrandMasterKhan]

think of it this way...

you have a water hose laying on the groud....

water is just trickling out of it...so you pick it up and sqeeze it....and the water Sprays out really fast.

(at low rpms the air entering the motor is moving slowly...too big of piping will not promote optimum air intake speed...smaller/shorter piping is better for faster flow @ low rpms.)

i hope that doesnt comfuzid anyone.

the same theory applies to exhaust.

[CougarDemon]

ahhh ok. i overlooked the thing about the air is flowing at the same amount so if the 2nd's did open its less rather than more for the primaries...i see now..thanks.

[FastCougar]

Someone please back me up on this ... I know it's theory, but it just feels so right in my thinking. The reason why we have the dip in the HP curve is because of the "lull" in the torque curve just below 2,800 RPMs. Part of this lull is due to reaching max efficiency of the long runners already somewhere around 2,400 - 2,500 RPMs. Another reason for the noticeable drop is because of the temporary loss of velocity when the IMRC opens, or should I say, SLAMS OPEN! There is not a gradual opening of the IMRC ... it's either on or off ... no in between. I think that a substantial mid range increase could be had by phasing open the IMRC between 2,400 - 3,200 based on load. I think this "ramping" of the secondary throttles will be more beneficial to creating a flatter or more increasing torque curve. Make sense?

Think of it this way: currently, the car is humming along at around 3,000 RPMs, the secondaries slam open. Prior to now, the velocity of the air has been high and then WHAM, a huge pressure drop occurs because we now have twice as much room to flow only slightly more amounts of air.

Question is, how can we slow the opening of the IMRC? What effects would this have if I step off the gas mid change? Will I increase pollution, thus failing a rolling road (dynamometer) emissions test?

I don't disagree with lowering the opening point, but I do disagree with the fact that this opening function should remain the same. My suggestion: lower the opening point to 2,400-2,500 RPMs and prolong that opening so that 100% opened secondaries isn't achieved till around 3,200. These numbers are just off the top of my head from recollection of dyno numbers & graphs ... exact numbers would come from extensive testing and dyno runs.

[PuckPuck]

That does seem to make sense in theory... building a circuitry to do it... HAVE FUN!!!


my solution to all of this... run 3.0L intake manifolds, rid yourself of the IMRC then have 01blkcat build you an IMRC black box to get rid of the CEL :)

[Frank]

I think the dip has a lot to do with intake resonance, not velocity - the short runners are tuned for max efficiency around 4500RPM and the long runners are most efficient around 2500RPM... there's no in-between (I think the Probe GT for instance had a 3 or 4 stage VRIS setup). Having the secondaries open gradually probably wouldn't change this, since the runner lengths are still the same.

[FastCougar]

I we will have to agree to disagree then ... I don't see how harmonics in the intake tract could overcome the vacuum created by the cylinders. Please explain this to me. Until you convince me otherwise, I am going to stick with my theory that it's a drop in vacuum associated with the split second drop in velocity/vacuum that occurs when you have not enough air to fill a volume that has just essentially doubled.

Think of it this way: You are sucking through a straw with your finger covering half the opening on the other end where the air is coming from. Now someone comes along and flicks your finger. If you don't start sucking nearly twice as fast, thus increasing the vacuum on your end, you are going to end up taking in less air.

The cylinders in the car are a fix volume and are taking in the same amount of air with each stroke. By increasing this interval of when strokes occur (increase RPM), we increase the engine's vacuum. With our engines, we are creating low end velocity by creating a restriction in the intake path. This is good only up to a point, when the engines need for air will out do it's supply. This is when the secondaries open. In our case, they open nearly instantly, doubling the amount of air the engine can ingest. Even at WOT, this opening of the secondaries happens in the blink of an eye ... at most over a 200-300 RPM increase. Now, unless we can instantly jump from 2,500 RPMs to 4,500 RPMs, which we can't, there will be a slowdown in the flow of air because the engine will need to build vacuum again because there has been a pressure drop. I think resonance has NOTHING to do with it, but I could be wrong ... feel free to explain why you think so.

This is the same principle behind choosing the correct size end tanks for an intercooler ... too much pressure drop across the intercooler could mean a measurable drop in boost, thus negating the intercooler's effect. This is seen time and time again in turbo applications where bigger isn't always better!

[yeehaw]

A suggestion for ramping the secondarys open: Use a small Piston on the cable to slow the opening (same concept as a shock absorber) I know they make small ones for applications like this.... You could prolly get one from a RC car3 catalouge.....



Darcy

[Frank]

This article gives more specific info on the effects of intake resonance and intake manifold design... I don't completely understand the physics involved, but if you do a search on google for intake runner length and intake resonance, you'll see terms like "slight supercharging effect" used a lot..

http://enaf1.tripod.com/teche.html

[NorCalCoug]

So, uh, anyone plug a vacuum gauge into their intake tract yet to see how the air pressure behaves at different RPM, just for ****s and grins? :) I have a vacuum gauge but it's Japanese and goes up to 80cm of mercury. I dunno what that equates to or if it's sensitive enough (or NOT sensitive enough!) to determine manifold vacuum.

[01blkcat]

Originally posted by: NorCalCoug
So, uh, anyone plug a vacuum gauge into their intake tract yet to see how the air pressure behaves at different RPM, just for ****s and grins? :) I have a vacuum gauge but it's Japanese and goes up to 80cm of mercury. I dunno what that equates to or if it's sensitive enough (or NOT sensitive enough!) to determine manifold vacuum.

I have that on the AutoTap extended... IIRC - I'll bring it tomorrow when I take the car out and see what I've got... I know for a fact that I have MAF Pressure, as it's one of the gauges on the virtual desktop.

[DemonSVT]

Slowing the IMRC down is the worst thing you could do.
All it does is make the dip in the power graph longer in rpm duration! (yes it's been well tested)

The dip in the curve is caused by the sudden lose of velocity. Prolonging the drop in velocity only prolongs the dip in the curve!

Also the short runners are tuned for a specific rpm. The are most efficient at around 2500-3000rpm & all done by 3500rpm. (I.E. they can not sustain power/flow enough air above 3500rpm!)
The more efficient the engine is (cfm draw) the lower the rpm point is that the primaries can sustain.

The short runners have no such "tuned" rpm range. The real powerband is controlled by the cams. Actually as is both powerbands!

You have to remember that the cams also shape the lower power band considering it is a dual pattern camshaft (primary & secondary lobes are different) When the primaries are the only valves being used you are running off only the primary cam lobes.
Altering the IMRC dynamics will not change this in any way!

So it's back to where we started.

IMO you should leave the IMRC operational. Lower the point to around 3000rpm at WOT & make then open as fast as possible.

If you have a 3L or Forced induction. Remove them and have a custom chip programmed to open them at 2500rpm (for the timing & fuel ramp up) and tune the many, many other aspects from there. (don't forget to rig a return spring)

[PuckPuck]

Originally posted by: DemonSVT


IMO you should leave the IMRC operational. Lower the point to around 3000rpm at WOT & make then open as fast as possible.



it is more than just RPM point that opens the secondaries.... MAF flow rate and TPS angle also play as a factor.... so making your own chip to forcibly open them at xxxx rpm may not be the best solution, as i'm sure the ECU takes in RPM, MAF flow rate and TPS angle in it's calculations before opening them up....

you can use test this using the secondaries light how to on TeamNECO, then watch the light and monitor the other readings with autotap... now play with throttle position and RPMs... when I did this i was able to get them to open at 4000 just as easily as 3400, however TPS angle and MAF are different for both....

and that is why getting a chip from a chip manufacturer to do this earlier opening and not making your own circuitry would be the only way to go (unless of course you yank them and just make the "black box")

[FastCougar]

Originally posted by: DemonSVT
Slowing the IMRC down is the worst thing you could do.
All it does is make the dip in the power graph longer in rpm duration! (yes it's been well tested)

The dip in the curve is caused by the sudden lose of velocity. Prolonging the drop in velocity only prolongs the dip in the curve!Where are these tests? Not that I don't believe you, but I would like to see these tests. My reason for doubt in this line of thinking is simple. If the "dip" is cuased by a sudden drop in velocity (which I have stated all along), then it only goes to reason that phasing in the secondaries would then lessen this effect and allow the engine to breath at the pace that it should be.

The reason why I think that Ford didn't do this is simple ... it would complicate things considerably considering what Pierre is saying. Since secondary actuation is dictated not only by RPM, but by load, this phasing would need to be dynamic. Creating such a system takes time and TONS of R&D to get it right and let's be frank ... Ford wasn't about to put that kind of R&D into an econo family sedan. The return on investment just isn't there.

In conclusion, I think that the best bet is to leave well enough alone until you can do a direct 3.0L swap and maximize performance with an ECU manipulator like TWEECER, once it is done being developed. Otherwise, you are left with 200hp/200tq ... I say that like it's a bad thing :naughty:

[DemonSVT]

Originally posted by: PuckPuck
1. it is more than just RPM point that opens the secondaries.... MAF flow rate and TPS angle also play as a factor.... so making your own chip to forcibly open them at xxxx rpm may not be the best solution, as i'm sure the ECU takes in RPM, MAF flow rate and TPS angle in it's calculations before opening them up....

2. you can use test this using the secondaries light how to on TeamNECO, then watch the light and monitor the other readings with autotap... now play with throttle position and RPMs... when I did this i was able to get them to open at 4000 just as easily as 3400, however TPS angle and MAF are different for both....

3. and that is why getting a chip from a chip manufacturer to do this earlier opening and not making your own circuitry would be the only way to go (unless of course you yank them and just make the "black box")

1. It's RPM & TPS. Nothing else. MAF voltage has nothing to do with it. Also all it looks for is the preset WOT voltage from the TPS.
There are 2 rpm points. RPM open at WOT and max RPM auto open.

2. Any one with Alex Pepper's setup can data log it in real time! It's one of the many Manufacturer's Enhanced Login features.
Much more reliable & accurate that a jimmy rigged light & looking at the innaccurate tach!

3. Eh??? I said a custom chip is the way to go and you say it's not and then say it is. Okay then...
Also making your own circuitry DOES work. I've done it. I stopped using it when I started Beta testing the Tweecer.

[DemonSVT]

Originally posted by: FastCougar
1. Where are these tests? Not that I don't believe you, but I would like to see these tests. My reason for doubt in this line of thinking is simple. If the "dip" is cuased by a sudden drop in velocity (which I have stated all along), then it only goes to reason that phasing in the secondaries would then lessen this effect and allow the engine to breath at the pace that it should be.

2. The reason why I think that Ford didn't do this is simple ... it would complicate things considerably considering what Pierre is saying. Since secondary actuation is dictated not only by RPM, but by load, this phasing would need to be dynamic. Creating such a system takes time and TONS of R&D to get it right and let's be frank ... Ford wasn't about to put that kind of R&D into an econo family sedan. The return on investment just isn't there.

3. In conclusion, I think that the best bet is to leave well enough alone until you can do a direct 3.0L swap and maximize performance with an ECU manipulator like TWEECER, once it is done being developed. Otherwise, you are left with 200hp/200tq ... I say that like it's a bad thing :naughty:
1. They were (are?) in the old CEG archives. Then Keyser redid it during one of his many dyno run binges. The graphs showed that a quick opening produced a very short hit to the powercurve. (less then 100rpm) Slowing down the point extended that dip to around 300rpm.

Actually I think I may have some charts where I did a similar test on my car. I'll have to look for those...

2. It's not load dependant. (see previous post) Also Ford didn't do it because they certainly tested it and saw the results. Also that crack about R&D is pretty lame. The CDW-27 platform was the largest cost global platform Ford ever did. It's also been Ford's top car in Europe for nearly a decade! (several times Europe's top car even)

3. Isn't that exactly what I said!!! I recommended leaving them in and only slightly lowering the rpm point at which they open.
BTW - I don't know if that last crack was at me, but I do have a Tweecer and before that had a "limited" self controllable IMRC setup since just after I removed the secondaries last March. So nyah, nyah... :biggrin:

Also why would just a direct 3L swap need this and not anything else? That makes no sense to say such a limiting statement.

[FastCougar]

1. That would be great. I would really like to visualize how this would work. BTW, how did you prolong the opening? I have opened a IMRC box and I think the best way would be to change the gearing on the motor connection. See attached image.

2. I stand behind my R&D comment. The Focus is a prime example! Sells like hotcakes in both the US and Europe. However, sales and popularity have nothing to do with it's R&D and it's release to the public. Actually, I may be wrong here ... perhaps that is the point ... release a car that is half-assed and let the masses do the R&D for you :rolleyes:.

What is the basis for my acusations? How about 10 recalls in the past 3 years (2000-2002)! Recalls, not TSB's ... Recalls where FORD is forced to admit a problem. I did a similar search and low and behold, the Contour has 10 Recalls as well, albeit over the entire production life the car in the US (6 years - 1995-2000). If they are not researching the simplist things like wheel bearings failing prematurely and causing wheel wobble, what makes you think that they researched the UIM extensively?

I have no proof of what I am saying, but merely pointing out a track record. Maybe they did extensive testing, but chances are that they didn't. From past experiences, they knew what worked and used what they knew. Why pay researches and eat into your budget to make 3-5 more hp for a family sedan? It doesn't make financial sense and we all know that Quality ISN'T Job1 ... the bottom line is and always will be Job1. Not only with Ford, but with any car maker.

3. I was agreeing with you in comment #3, sorry I didn't quote you ;)

As for the "direct" swapping of the 3.0, I have a gut feeling that the late model 3.0 with the plastic UIM suffers less from heat soak and may in fact flow better numbers in a forced induction environment. Besides, less moving parts (secondaries) = less chance of something going wrong and less to worry about. If I read correctly in this months MotorTrend, Mazda retained the 3.0L's UIM design. Jag massaged it quite a bit in their version for yet even more power.