Ecoboost engine question

[Bmach]

With the Eco doing so well and loved by many and bragged about by Ford. Why is it not offered in the F250 ?

I love mine but I'm curious.

[Wes_Tausend]

...

Thicker fuel??

Boosted engines have thicker air. :B

Wes
...

[pronstar]

^^^ to your point, I love the fact that we have seemingly more choices than ever when it comes to equipping these trucks.

[bmanning]

Common sense is invaluable in life but for something as complicated as an ICE in 2014, gas or diesel, a lot more than common sense is needed to make an informed choice as to what works best in a given application.

Put another way, one size doesn't fit all and never really has.

[Hannibal]

I'll keep that in mind if I ever need an 18 wheeler. :B

[bigblue1234]

Just A fact,thicker the fuel more power,thinner the fuel less power. Just common sense.How many 18 wheelers have you seen today with gas engine?

[itguy08]

Wes Tausend wrote:
...

I think premium simply allows the engine to produce more power. The high compression caused by boost lets the EB efficiently take advantage of higher octane fuel. I don't think it has to burn premium, but it is a case where it pays off in performance. FWIW, my old 5.0L Mustang also suggested premium for better performance, but I never used it. The DWs Corvette demanded premium, and that is what it got.

I think the Ford ecoboost has a detonation sensor because it could detonate if the computer had no way to know it was starting. But with the sensor, the fast computer can reliably compensate and the EB can precariously run at max just under the detonation threshold.

I have owned an Ecoboost a hair over 4 years and 69,900 miles now. It's the car version in a Taurus SHO.

The EB will definitely run perfectly fine in all conditions on regular gas. That's what I have been feeding mine all this time. Been in the freezing cold, 100+ heat of TX, LA, FL and never an issue. Sometimes under a heat soak and wanting max power you can feel it not working 100% smoothly but it will still pull like crazy. This year I played around with 89 during the summer and she smoothed out well. Premium still is the smoothest ride and you can feel it work a little better but I get no more fuel economy so I don't run it much.

The EB will most definitely detonate given the right circumstances. Some of us with early builds of the car engine had knock sensors that would chafe and cause erroneous readings. I had 2 incidences of rather violent knocking before they replaced the sensor @ 30k. Sounded like you were shaking a can of Krylon in the passenger seat.

It definitely is a fine engine.

[Wes_Tausend]

...

Turtle,

At this point, I think you are entirely correct about one thing for sure. Gasoline-DI(GDI) probably does not inject after TDC according to any info I found either. It seems a blatant enough mistake on my part, that I appreciate your very kind reply.

I don't know a lot about diesel, but I think they do inject more fuel after the initial charge during continued combustion. Apparently this won't work as well with gasoline, although I wouldn't entirely rule it out. The web info on GDI is kind of inconsistant and/or sketchy IMO.

On the other hand, I'm going to take the position of Devils Advocate to try to resolve some questions I still have, so if you will parden me for the sake of argument...

Definition:
Brake specific fuel consumption (BSFC) is a measure of the fuel efficiency of a shaft reciprocating engine. It is the rate of fuel consumption divided by the power produced.

First:
The 3.5L EB engine seems quite efficient under power, and comparable to NA offerings in the F-150. How can this be if excess fuel is wasted just for TC anti-detonation cooling?

One other glaring question is:
What happens to my assumed recovered energy contained in the greater loss of heat energy between a NA (naturally aspirated) engine and TC (turbo charged)? This is supposing that for identical fuel, the TC engine recovers some additional energy and therefore releases cooler exhaust than the NA engine which loses all remaining gaseous heat energy after the combustion stroke. It follows, and is my belief that the TC therefore either delivers just slightly more hp for same said fuel, or the same hp for slightly less fuel.

Wes
====================================================================

Turtle n Peeps wrote:
Wes is does not matter if it's a race engine or street engine or carb or DI. A turbo/supercharged engine will always have a higher BSFC figure than a N/A engine.

I'm going to try to stay with my speculation that the TC BSFC does not necessarily specifically demand more fuel for high efficiency consumer use, and that there can be, and should be, a difference between relatively "crude" TC race engines and the latest, highly developed TC performance production vehicles.

I don't know exactly how Ford does it, but it appears to me that they have, by necessity, carefully tuned out detonation by other means rather than flooding the engine with excess rich fuel. A race TC engine owner often does not care if fuel is wasted (within reason) and the easiest pocket solution to intake charge cooling is normally chosen via excess fuel. I even ran my 2-stroke dirtbikes rich for similar reasons, but there was no easy safe alternative at the time. OTOH, modern 2-stroke DI outboards are extraordinarily fuel efficient in comparison.

Turtle n Peeps wrote:
The turbo, or belt drive supercharger (pump) needs power to turn the compressor blades or rotors. That power just does not come out of thin air. It comes from fuel burnt and this is why a supercharged engine will have a higher BSFC.

I agree this is absolutely true for SC, the final exhaust, while under power, will reflect higher heat per-unit-hp delivered partly because more fuel must be burned to drive the compressor. No gaseous tail-pipe heat energy is recovered in SC after "thee standard recovery" from piston thrust pressure during combustion.

But I believe TC is different. The final "thow-away" exhaust is cooler, after passing through the turbo, designating that some heat energy has gone elsewhere besides tail-pipe waste or piston thrust. This drop in exhaust temp represents a large percent of the energy delivered to the impeller to compress the intake. It isn't really free energy... it's additional recovered energy from the same amount of fuel. There have even been uncommon cases where a turbo not only drives a compressor, but is also geared directly to the main propulsion shaft to take advantage of this principle. Ideally (not possible) the exhaust would exit at ambient surrounding air temp, and all burned fuel energy would be converted to rotational power ala 100% efficiency.

Turtle n Peeps wrote:
It has been erroneously stated many times, and sometimes in big publications that turbo's are "Free Horsepower." Nothing could be further from the truth. Pumps need energy to work and that energy comes from fuel.
It takes a lot of HP to turn pumps. Whether it's a water pump or an oil pump or an air pump. In the case of an ICE that power comes from fuel.

I agree, see above paragraph. I'm just saying more of the available, normally wasted energy from the fuel is put to work, as in TC can be more efficient than SC, and theoretically just as efficient, or rather more efficient, than NA. This hasn't been the case in the past but it is now the newest game in town.

Turtle n Peeps wrote:
Now let me talk about DI engines and the way they function. There is a wide misconception that DI engines can't pre-ignite because they inject the fuel after TDC. This is just not the case for several reasons.
Without writing a big book about the subject this article explains it better than I can.

I'm not absolutely sure the Wiki link is entirely correct or complete. It does strongly suggest that all stoic and power gasoline DI mixes must be accomplished by completed injection during the intake stroke to assure a homogenous mix. All other web sources seem to agree at this point. This homogenous mix requirement may be true of gasoline whereas diesel is more forgiving. But, logically, I doubt it.

Since ultra-lean gas mixes can be successfully ignited by using a stratified charge (rich near the sparkplug), I don't really see why some additional gasoline injection could not take place after TDC if it works in diesels. The ideal homogenous mix idea is that all fuel molecules are nearby all oxygen molecules, and that speedy combustion can therefore be completed during the short high speed power stroke. But I will guess, with carefully arranged "swirl" the molecular match is also quite good. I have to ask, why would diesel be that much more different than gasoline?

Turtle n Peeps wrote:
In short, a DI engine has 3 main modes:

#1. Ultra lean burn. (The DI engines see this mode VERY, VERY seldom. Going down a slight hill or during a medium to low speed at a steady speed are some times that an engine might this mode. The fuel is injected during the latter parts of the compression stroke)

#2. Stoichiometric mode. (In this mode the engine injects the fuel exactly the same "time" as an old bank to bank system; during the intake stroke. Nothing new here, same ol, same ol of yesteryear.)

#2. Full power mode. (Fuel is again injected during the intake stroke. The fuel curve goes to full rich mixture to prevent detonation.

Ultra lean burn has oxygen left for the taking. All fuel is burned. Can after-TDC fueling take advantage of this "left-over oxygen" in a power type cycle?

Stoichiometric mode. I agree this should best take place as homogenous, and perhaps swirled for the most consistant flame front. There appears no reason to do it otherwise.

Full power mode. Rather than excessively enrichen the mix to prevent detonation ala "firehose", the fuel is very briefly increased just barely to the point that all oxygen molecules "can find" a fuel companion, even if just a few raw fuel molecules are left. At this time the maximum possible combustion takes place for all available air. My guess is that this is seldom done nowadays with any unburned fuel being anti-EPA. I think the term, "Full Power Mode" is becoming obsolete, or nearly so.

Turtle n Peeps wrote:
For those that still want to debate the facts please answer this question. Why does Ford recommend premium fuel for the Ecoboost when towing? Why would they do that? After all, if the Ecoboost can't detonate why do we need premium fuel for it during heavy load and HP? The only reason to cut back timing or use premium is to prevent detonation.

Or this question: Why does Ford ecoboost have a detonation sensor if it can't detonate?

I think premium simply allows the engine to produce more power. The high compression caused by boost lets the EB efficiently take advantage of higher octane fuel. I don't think it has to burn premium, but it is a case where it pays off in performance. FWIW, my old 5.0L Mustang also suggested premium for better performance, but I never used it. The DWs Corvette demanded premium, and that is what it got.

I think the Ford ecoboost has a detonation sensor because it could detonate if the computer had no way to know it was starting. But with the sensor, the fast computer can reliably compensate and the EB can precariously run at max just under the detonation threshold.

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

I think the 3.5L Ford EB lives on the edge and Ford thinks it can reliably keep doing it and survive. This latest technology is amazing and I have much to learn about it yet.

Wes
...

[jus2shy]

Turtle n Peeps wrote:
Wes is does not matter if it's a race engine or street engine or carb or DI. A turbo/supercharged engine will always have a higher BSFC figure than a N/A engine.

The turbo, or belt drive supercharger (pump) needs power to turn the compressor blades or rotors. That power just does not come out of thin air. It comes from fuel burnt and this is why a supercharged engine will have a higher BSFC.

It has been erroneously stated many times, and sometimes in big publications that turbo's are "Free Horsepower." Nothing could be further from the truth. Pumps need energy to work and that energy comes from fuel.
It takes a lot of HP to turn pumps. Whether it's a water pump or an oil pump or an air pump. In the case of an ICE that power comes from fuel.

Now let me talk about DI engines and the way they function. There is a wide misconception that DI engines can't pre-ignite because they inject the fuel after TDC. This is just not the case for several reasons.
Without writing a big book about the subject this article explains it better than I can.

In short, a DI engine has 3 main modes:

#1. Ultra lean burn. (The DI engines see this mode VERY, VERY seldom. Going down a slight hill or during a medium to low speed at a steady speed are some times that an engine might this mode. The fuel is injected during the latter parts of the compression stroke)

#2. Stoichiometric mode. (In this mode the engine injects the fuel exactly the same "time" as an old bank to bank system; during the intake stroke. Nothing new here, same ol, same ol of yesteryear.)

#2. Full power mode. (Fuel is again injected during the intake stroke. The fuel curve goes to full rich mixture to prevent detonation.

For those that still want to debate the facts please answer this question. Why does Ford recommend premium fuel for the Ecoboost when towing? Why would they do that? After all, if the Ecoboost can't detonate why do we need premium fuel for it during heavy load and HP? The only reason to cut back timing or use premium is to prevent detonation.

Or this question: Why does Ford ecoboost have a detonation sensor if it can't detonate?

That's basically what I witnessed with my LNF motor that GM employed in the Sky. Everyone talks about Ecoboost this and that, however GM started this game in the US, then the VW corp had TFSI which is also the same tech (However GM had the better setup with 3 lumps in the cam driving the high pressure fuel pump). Then Ford had the foresight to come up with some slick branding known as "Ecoboost". I remember when some enthusiast garages were tuning the LNF, they complained of not being able to run the injectors at 100% because if they did, they would be washing the side of the piston for part of the stroke, they mentioned only being able to run the injector through 70% of a stroke to ensure fuel was spraying well into the piston bowl. It was also interesting to hear the different pulses of the high pressure fuel pump from the early direct injection motors. You could tell when it was injecting, when it wasn't and it had a distinct tick at idle.

[Turtle_n_Peeps]

Wes is does not matter if it's a race engine or street engine or carb or DI. A turbo/supercharged engine will always have a higher BSFC figure than a N/A engine.

The turbo, or belt drive supercharger (pump) needs power to turn the compressor blades or rotors. That power just does not come out of thin air. It comes from fuel burnt and this is why a supercharged engine will have a higher BSFC.

It has been erroneously stated many times, and sometimes in big publications that turbo's are "Free Horsepower." Nothing could be further from the truth. Pumps need energy to work and that energy comes from fuel.
It takes a lot of HP to turn pumps. Whether it's a water pump or an oil pump or an air pump. In the case of an ICE that power comes from fuel.

Now let me talk about DI engines and the way they function. There is a wide misconception that DI engines can't pre-ignite because they inject the fuel after TDC. This is just not the case for several reasons.
Without writing a big book about the subject this article explains it better than I can.

In short, a DI engine has 3 main modes:

#1. Ultra lean burn. (The DI engines see this mode VERY, VERY seldom. Going down a slight hill or during a medium to low speed at a steady speed are some times that an engine might this mode. The fuel is injected during the latter parts of the compression stroke)

#2. Stoichiometric mode. (In this mode the engine injects the fuel exactly the same "time" as an old bank to bank system; during the intake stroke. Nothing new here, same ol, same ol of yesteryear.)

#2. Full power mode. (Fuel is again injected during the intake stroke. The fuel curve goes to full rich mixture to prevent detonation.

For those that still want to debate the facts please answer this question. Why does Ford recommend premium fuel for the Ecoboost when towing? Why would they do that? After all, if the Ecoboost can't detonate why do we need premium fuel for it during heavy load and HP? The only reason to cut back timing or use premium is to prevent detonation.

Or this question: Why does Ford ecoboost have a detonation sensor if it can't detonate?

[Wes_Tausend]

Engineer9860 wrote:
The whole reason for the turbos on the Ecoboost engine are to fool a small displacement engine into thinking it is a large displacement engine. Same for turbo diesels.

The Ecoboost's low speed efficiency comes from its small displacement not its turbos.

You can never defy the laws of nature. Fuel energy is converted to heat. Heat is converted to horsepower. How an engine does this specifies how fuel efficient it will be. At low horsepower demand situations a small displacement engine will be more efficient because fuel is not needed merely to rotate large engine parts. In low horsepower demand situations a large displacement engine loses efficiency because energy is needed just to move it's more, and larger parts.

In high horse power demand situations all of the above no longer applies because both engines are working at capacity. In low horsepower demand situations the small displacement engine will focus a smaller percentage of the fuel burned on actually turning the engine parts. In the high horsepower demand situation a greater percentage of the work the engine is doing goes to the actual work being performed.

There is no free lunch. At the end of the day a certain level of fuel will still be needed to move a heavy brick through the air while its tires are trying to resist rolling. This is constant no matter what is under the hood.

Exactly! Well put.

Wes
...

[otrfun]

8iron wrote:
Which is why Ford detuned the Superduty version of the 6.2 for durability. Speaks to duty cycles expected from the f250/350 vs the lighter duty f150.

I hear ya--makes sense. Not that I believe everything I see, read or watch, but if one believes only a fraction of Ford's promotional video for the 3.5 Ecoboost, it's still very impressive. Honestly, I can't imagine how a "super-duty duty-cycle" could surpass that kind of abuse. Again, I'm not saying this video is any more than outstanding marketing, but I'm sure it's one of the major reasons why the 3.5 Ecoboost has been such a kick-ass success for Ford.

[8iron]

Krusty wrote:

otrfun wrote:

goducks10 wrote:

otrfun wrote:

goducks10 wrote:
My guess is that the 3.5 is maxed out with the 11,300lb tow rating in an F150. Add the extra weight of the F250/350 and the 3.5 would have a hard time reaching the 15,000+lb tow rating offered with the 6.2. It works fine in it's own element.

The 3.5 Ecoboost has 15 lbs. more torque than the 6.2, not to mention the 6.2 develops max torque at a relatively high 4500 RPM vs. the 3.5 Ecoboosts's much lower, diesel-like, 2500 rpm. I would think the limiting factor (ref tow capacity) for the 3.5 Ecoboost F150 is the 1/2 ton drivetrain and suspension.

Concerns about the 3.5 Ecoboost duty-cycle and fuel economy aside, I believe the 3.5 Ecoboost's torque characteristics would provide much better realworld performance (to include towing) than a 6.2 in a F250/350 chassis. Torque does all the work. The 3.5 Ecoboost has more and at a much lower RPM than the 6.2.

IMO the 3.5 is maxed out for stress in the F150. Do you really think the 3.5 in a 7-800+lb heavier truck can pull a 15,700lb 5th wheel? Even in the HD F150 it's still 11,300lb max towing. And the HD F150 has payloads equal to the F250 in certain configs. So with your way of thinking the HD F150 3.5 should be able to tow 13,000lbs with the 3.5. Why didn't Ford up the tow rating in the HD F150? Just because it has more torque at lower rpms doesn't mean it's internals are up to heavier towing. Why would Ford waste their engineering money on building a 6.2 for their HD trucks if the 3.5 was up to the task.

In the context of this debate, I think you have to compare these two engines in the context of them using the same chassis and drivetrain. No, the F150 3.5 Ecoboost cannot tow 13,000 lbs. Why? Because the F150's 1/2 ton drivetrain and suspension won't support it, not because of the engine.

Would a 6.2 mounted in an F150 chassis support more tow weight? If you say, yes, than how and why? The 6.2 puts out less torque than the 3.5 Ecoboost. Torque tows trailers, not HP.

The 3.5 Ecoboost engine is designed to put out 420 ft. lb. of torque. The 6.2 is designed to put out 405 ft. lbs. of torque. IMO, torque is torque. Is 1 ft. lb. of higher displacement V8 torque somehow "better" than 1 ft. lb. of turbo-charged, V6 torque? If so, can you explain how and why?

The fact the 3.5 Ecoboost has more torque than the 6.2 is not even the real clincher. The real clincher is the fact the torque on the 3.5 Ecoboost is output at nearly half the RPM's of the 6.2. In the realworld this makes the 3.5 Ecoboost much more useful and desirable from a drivability perspective. This is why diesels are so, so addictive. This is also why the Ecoboost has been such a run-away success for Ford. The 3.5 Ecoboost does one heckuva fine job of emulating a diesel engine's torque curve.

For what its worth, the 6.2L in the F150 puts out 434 ft/lbs of torque

Which is why Ford detuned the Superduty version of the 6.2 for durability. Speaks to duty cycles expected from the f250/350 vs the lighter duty f150.

[otrfun]

Krusty wrote:
For what its worth, the 6.2L in the F150 puts out 434 ft/lbs of torque

The 6.2 used in the Ford Super Duty's only produce 405 ft. lbs. of torque.

Nonetheless, it's interesting to note that the F150 3.5 Ecoboost has a slightly higher tow capacity than the F150 6.2 in most configurations.

[Krusty]

otrfun wrote:

goducks10 wrote:

otrfun wrote:

goducks10 wrote:
My guess is that the 3.5 is maxed out with the 11,300lb tow rating in an F150. Add the extra weight of the F250/350 and the 3.5 would have a hard time reaching the 15,000+lb tow rating offered with the 6.2. It works fine in it's own element.

The 3.5 Ecoboost has 15 lbs. more torque than the 6.2, not to mention the 6.2 develops max torque at a relatively high 4500 RPM vs. the 3.5 Ecoboosts's much lower, diesel-like, 2500 rpm. I would think the limiting factor (ref tow capacity) for the 3.5 Ecoboost F150 is the 1/2 ton drivetrain and suspension.

Concerns about the 3.5 Ecoboost duty-cycle and fuel economy aside, I believe the 3.5 Ecoboost's torque characteristics would provide much better realworld performance (to include towing) than a 6.2 in a F250/350 chassis. Torque does all the work. The 3.5 Ecoboost has more and at a much lower RPM than the 6.2.

IMO the 3.5 is maxed out for stress in the F150. Do you really think the 3.5 in a 7-800+lb heavier truck can pull a 15,700lb 5th wheel? Even in the HD F150 it's still 11,300lb max towing. And the HD F150 has payloads equal to the F250 in certain configs. So with your way of thinking the HD F150 3.5 should be able to tow 13,000lbs with the 3.5. Why didn't Ford up the tow rating in the HD F150? Just because it has more torque at lower rpms doesn't mean it's internals are up to heavier towing. Why would Ford waste their engineering money on building a 6.2 for their HD trucks if the 3.5 was up to the task.

In the context of this debate, I think you have to compare these two engines in the context of them using the same chassis and drivetrain. No, the F150 3.5 Ecoboost cannot tow 13,000 lbs. Why? Because the F150's 1/2 ton drivetrain and suspension won't support it, not because of the engine.

Would a 6.2 mounted in an F150 chassis support more tow weight? If you say, yes, than how and why? The 6.2 puts out less torque than the 3.5 Ecoboost. Torque tows trailers, not HP.

The 3.5 Ecoboost engine is designed to put out 420 ft. lb. of torque. The 6.2 is designed to put out 405 ft. lbs. of torque. IMO, torque is torque. Is 1 ft. lb. of higher displacement V8 torque somehow "better" than 1 ft. lb. of turbo-charged, V6 torque? If so, can you explain how and why?

The fact the 3.5 Ecoboost has more torque than the 6.2 is not even the real clincher. The real clincher is the fact the torque on the 3.5 Ecoboost is output at nearly half the RPM's of the 6.2. In the realworld this makes the 3.5 Ecoboost much more useful and desirable from a drivability perspective. This is why diesels are so, so addictive. This is also why the Ecoboost has been such a run-away success for Ford. The 3.5 Ecoboost does one heckuva fine job of emulating a diesel engine's torque curve.

For what its worth, the 6.2L in the F150 puts out 434 ft/lbs of torque