FlexFuel Ecoboost

Status
Not open for further replies.
I've wondered this myself...
or really, why don't they just make ALL the cars flex capable, even knowing full-well most folks won't/cant take advantage of it.

we're talking maybe $100 difference in their costs to build the car.(roughly what the aftermarket sensors cost, I'm sure an OEM can get 'em much cheaper in bulk.
 
In a very general, broad sense, and without going into any detail, I would say that the Ecoboost engines are so very specifically tuned that Ford is not going to muck it up by throwing E85 into the mix. Just my opinion. No facts.
 
Last edited:
It has everything to do with direct injection and the way the system operates with a high pressure fuel pump. In its basic form HPFP is a fixed displacement pump with no way to vary the volume of fuel necessary to adjust for the difference in BTU value between E85 and E10 or any mixture in between to maintain an AFR within acceptable burn limmits for engine protection and emissions compliance. There are no directed injected engines made by any manufacturer besides Mercedes that advertise E85 capability and they have significant long term issues.

E85 compatible vehicles all use electric variable displacement/variable voltage pumps that along with adjusting the pulse width of the injectors can inject more or less fuel to maintain the AFR.

HPFP are cam driven fixed displacement piston pumps that are feed by a electric fuel pump. They can not adjust volume of fuel. For example, E85 has 2/3 the energy of E10, therefore the HPFP would have to be able to deliver 2/3 more fuel at the maximum fuel demand rate to maintain enough fuel pressure and volume to provide enough fuel to maintain the AFR. And it simply can’t. Usually HPFP have a 30% over volume design, that’s it.

If you place water under a vacuum at room temperature it will boil. The same happens to the fuel when the HPFP starves for fuel because it’s putting more out than it can get from the electric pump or the demand is so great it’s loosing in the rail or a combination of both. The fuel is under a vacuum and the boiling “bubble pop” takes a small micron of metal away from the piston or the cylinder wall and eventually wears the pump enough to get leak by. Either way, that boiling or cavitation, and E85 being very dry and lacking lubricity kills HPFP’s and then usually an injector or two.
 
Last edited:
Just my opinion , but a person should ear corn and burn gasoline . The ethanol fuel idea / industry is just a huge boondoggle & subsidy to the agriculture industry .

If you are going to do ethanol fuel , make sure it will be economically viable w/o subsidies & use something for the raw product that we or our livestock do not eat .

Noe , if a person wishes to go " green " , make bio diesel from waste oil .
 
Ethanol use across the nation does not add up so they probably don't want to bother with it? Does Chrysler make anything that is E compatable?

We have either E10 or E85 here.. No in between. Out west where they grow more corn than here, they have E15, E20 etc. that bring the cost down without taking a hit in mileage, and thus making it's use pointless. I would use it in this case.. (Can't remember the BITOG member who talked about this.) I do find it odd that the larger corn producers have the option to use LESS ethanol. Somewhat like a CEO of a tobacco company not using tobacco.

I do know some local farmers that were "upset" when fuel prices were low (that fall after fuel was $4+ a gallon) because that meant they'd get less for their corn. I am just surmising that they disregarded THEIR costs to pick the stuff, but I am not sure..
 
Originally Posted By: rodinator1234
There are no directed injected engines made by any manufacturer besides Mercedes that advertise E85 capability and they have significant long term issues.

E85 compatible vehicles all use electric variable displacement/variable voltage pumps that along with adjusting the pulse width of the injectors can inject more or less fuel to maintain the AFR.


You might want to look at GM's L83 (LT1 based) Gen V motor.
 
Originally Posted By: rodinator1234
It has everything to do with direct injection and the way the system operates with a high pressure fuel pump. In its basic form HPFP is a fixed displacement pump with no way to vary the volume of fuel necessary to adjust for the difference in BTU value between E85 and E10 or any mixture in between to maintain an AFR within acceptable burn limmits for engine protection and emissions compliance. There are no directed injected engines made by any manufacturer besides Mercedes that advertise E85 capability and they have significant long term issues.

E85 compatible vehicles all use electric variable displacement/variable voltage pumps that along with adjusting the pulse width of the injectors can inject more or less fuel to maintain the AFR.

HPFP are cam driven fixed displacement piston pumps that are feed by a electric fuel pump. They can not adjust volume of fuel. For example, E85 has 2/3 the energy of E10, therefore the HPFP would have to be able to deliver 2/3 more fuel at the maximum fuel demand rate to maintain enough fuel pressure and volume to provide enough fuel to maintain the AFR. And it simply can’t. Usually HPFP have a 30% over volume design, that’s it.

If you place water under a vacuum at room temperature it will boil. The same happens to the fuel when the HPFP starves for fuel because it’s putting more out than it can get from the electric pump or the demand is so great it’s loosing in the rail or a combination of both. The fuel is under a vacuum and the boiling “bubble pop” takes a small micron of metal away from the piston or the cylinder wall and eventually wears the pump enough to get leak by. Either way, that boiling or cavitation, and E85 being very dry and lacking lubricity kills HPFP’s and then usually an injector or two.



Assuming E85 has two thirds the energy of E10, then the HPFP would have to deliver one half more fuel, not two thirds more.
(Two thirds plus one third = one; and one third is half of two thirds, so 50% more not 67% more).

The HPFP has a 30% over volume design (130%) which would be 20% short of being able to run E85. Does not seem that insurmountable to me.
 
Originally Posted By: dlundblad
Ethanol use across the nation does not add up so they probably don't want to bother with it? Does Chrysler make anything that is E compatable?


Their most common engine, the Pentastar. I think they took the option out last year, but their 4 cylinder engines still have it. There are 5 million of them on the road. Every Dodge Caravan taxi I see has a FlexFuel badge.
 
Last edited:
Implying that DI engines cannot vary their fuel delivery is a bit disingenuous. As noted above GM has DI engines that are flex fuel. I am sure they can vary their injector pulse width in order to modulate fuel delivery as virtually any fuel injected vehicle does.

Frankly, IMO Ford is a bit more knowledgeable than many here and understands their Ego boosters are tuned a bit closer to the ragged edge than the average engine. Regular E10 varies tremendously from station to station and is probably all they could consider within their factory tune.
 
Originally Posted By: rodinator1234

HPFP are cam driven fixed displacement piston pumps that are feed by a electric fuel pump. They can not adjust volume of fuel. For example, E85 has 2/3 the energy of E10, therefore the HPFP would have to be able to deliver 2/3 more fuel at the maximum fuel demand rate to maintain enough fuel pressure and volume to provide enough fuel to maintain the AFR. And it simply can’t. Usually HPFP have a 30% over volume design, that’s it.


Ford's HPFP can vary both the volume and pressure of the fuel.

Ford HPFP

Quote:

The high-pressure system consists of a high-pressure fuel pump that is mechanical and driven by a special four-point camshaft lobe that is only for pump operation. The plunger action of the high-pressure pump boosts fuel pressure up to 2,150 psi. The high-pressure fuel is in the metal line leaving the pump to the rails as well as the fuel rails. There is also no return line in the high-pressure system. The high-pressure pump mounts on the left valve cover. Pressure in the high-pressure system swings widely with rpm and demand. Pressures here will swing from as low as 1,000 psi to 2,150 psi depending on conditions. Pressure is controlled by balancing the volume through the pump and into the rail versus the volume passing through the injectors. One complete revolution of the camshaft produces four strokes of the high-pressure pump. At maximum, these four strokes equal 1 cc of fuel delivered to the rail. If met with a dead end, that 1 cc of fuel would raise the rail pressure by about 800 psi. The injector cycling will vent that fuel into the cylinders at around 21 cc per second. The PCM raises and lowers the high-side fuel pressure by pulsing the fuel inlet valve (solenoid) on the side of the pump. The inlet valve controls not only the amount of fuel that enters the pump chamber, but also the amount that bleeds back into the low-pressure system when the pump’s plunger pushes the fuel out. The more the pump is filled, and the less that bleeds back into the low side, the higher the pressure will be in the rails. The PCM monitors a fuel rail pressure sensor to determine the needed action at the volume regulator. The pressure sensor is mounted to the top of the left-hand rail.


I've personally witnessed (via Torque and and OBD scanner) the pressure cycles of the HPFP pump.

As to why no Flex Fuel Ecoboosts - no idea. Probably lots of engineering for near 0 benefit. In the right hands the EB's are capable of great power.
 
Originally Posted By: 04SE
Originally Posted By: rodinator1234
There are no directed injected engines made by any manufacturer besides Mercedes that advertise E85 capability and they have significant long term issues.

E85 compatible vehicles all use electric variable displacement/variable voltage pumps that along with adjusting the pulse width of the injectors can inject more or less fuel to maintain the AFR.


You might want to look at GM's L83 (LT1 based) Gen V motor.


I don’t think GenerL Motors advertises this as a flex fuel compatable engine. Check it out.
 
Originally Posted By: Crispysea
Originally Posted By: dlundblad
Ethanol use across the nation does not add up so they probably don't want to bother with it? Does Chrysler make anything that is E compatable?


Their most common engine, the Pentastar. I think they took the option out last year, but their 4 cylinder engines still have it. There are 5 million of them on the road. Every Dodge Caravan taxi I see has a FlexFuel badge.


Pentastar engines are not direct injected, neither are Tigershark engines. Do a quick google search if you don’t believe me. Prove me wrong, by all means.
 
Originally Posted By: itguy08
Originally Posted By: rodinator1234

HPFP are cam driven fixed displacement piston pumps that are feed by a electric fuel pump. They can not adjust volume of fuel. For example, E85 has 2/3 the energy of E10, therefore the HPFP would have to be able to deliver 2/3 more fuel at the maximum fuel demand rate to maintain enough fuel pressure and volume to provide enough fuel to maintain the AFR. And it simply can’t. Usually HPFP have a 30% over volume design, that’s it.


Ford's HPFP can vary both the volume and pressure of the fuel.

Ford HPFP


What
Quote:

The high-pressure system consists of a high-pressure fuel pump that is mechanical and driven by a special four-point camshaft lobe that is only for pump operation. The plunger action of the high-pressure pump boosts fuel pressure up to 2,150 psi. The high-pressure fuel is in the metal line leaving the pump to the rails as well as the fuel rails. There is also no return line in the high-pressure system. The high-pressure pump mounts on the left valve cover. Pressure in the high-pressure system swings widely with rpm and demand. Pressures here will swing from as low as 1,000 psi to 2,150 psi depending on conditions. Pressure is controlled by balancing the volume through the pump and into the rail versus the volume passing through the injectors. One complete revolution of the camshaft produces four strokes of the high-pressure pump. At maximum, these four strokes equal 1 cc of fuel delivered to the rail. If met with a dead end, that 1 cc of fuel would raise the rail pressure by about 800 psi. The injector cycling will vent that fuel into the cylinders at around 21 cc per second. The PCM raises and lowers the high-side fuel pressure by pulsing the fuel inlet valve (solenoid) on the side of the pump. The inlet valve controls not only the amount of fuel that enters the pump chamber, but also the amount that bleeds back into the low-pressure system when the pump’s plunger pushes the fuel out. The more the pump is filled, and the less that bleeds back into the low side, the higher the pressure will be in the rails. The PCM monitors a fuel rail pressure sensor to determine the needed action at the volume regulator. The pressure sensor is mounted to the top of the left-hand rail.


I've personally witnessed (via Torque and and OBD scanner) the pressure cycles of the HPFP pump.

As to why no Flex Fuel Ecoboosts - no idea. Probably lots of engineering for near 0 benefit. In the right hands the EB's are capable of great power.


What you witness is the fuel pressure regulator varying pressure in the rail based on demand. Fixed volume pumps driven by cams vary only in RPM the regulator manages pressure. Injector, pulse width, duty cycle and fuel load demand all calculate into the required fuel demand for performance and emessions compliance which is also a huge consideration.
 
Originally Posted By: rodinator1234
Originally Posted By: Crispysea
Originally Posted By: dlundblad
Ethanol use across the nation does not add up so they probably don't want to bother with it? Does Chrysler make anything that is E compatable?


Their most common engine, the Pentastar. I think they took the option out last year, but their 4 cylinder engines still have it. There are 5 million of them on the road. Every Dodge Caravan taxi I see has a FlexFuel badge.


Pentastar engines are not direct injected, neither are Tigershark engines. Do a quick google search if you don’t believe me. Prove me wrong, by all means.


I didn’t say they were DI. I said they were E85 compatible.
 
Originally Posted By: rodinator1234

What you witness is the fuel pressure regulator varying pressure in the rail based on demand. Fixed volume pumps driven by cams vary only in RPM the regulator manages pressure. Injector, pulse width, duty cycle and fuel load demand all calculate into the required fuel demand for performance and emessions compliance which is also a huge consideration.


Reading how the Ford system works yes, it's a fixed volume pump. Pressure and volume is controlled by the amount of bleedback from the pump back into the low pressure side of things.

Quote:
The injector cycling will vent that fuel into the cylinders at around 21 cc per second. The PCM raises and lowers the high-side fuel pressure by pulsing the fuel inlet valve (solenoid) on the side of the pump. The inlet valve controls not only the amount of fuel that enters the pump chamber, but also the amount that bleeds back into the low-pressure system when the pump’s plunger pushes the fuel out.
 
Originally Posted By: rodinator1234
Originally Posted By: 04SE
Originally Posted By: rodinator1234
There are no directed injected engines made by any manufacturer besides Mercedes that advertise E85 capability and they have significant long term issues.

E85 compatible vehicles all use electric variable displacement/variable voltage pumps that along with adjusting the pulse width of the injectors can inject more or less fuel to maintain the AFR.


You might want to look at GM's L83 (LT1 based) Gen V motor.


I don’t think GenerL Motors advertises this as a flex fuel compatable engine. Check it out.


GM's L83 is advertised as E85 compatible.

 
Originally Posted By: gonefishing
Originally Posted By: rodinator1234
Originally Posted By: 04SE
Originally Posted By: rodinator1234
There are no directed injected engines made by any manufacturer besides Mercedes that advertise E85 capability and they have significant long term issues.

E85 compatible vehicles all use electric variable displacement/variable voltage pumps that along with adjusting the pulse width of the injectors can inject more or less fuel to maintain the AFR.


You might want to look at GM's L83 (LT1 based) Gen V motor.


Again you

I don’t think GenerL Motors advertises this as a flex fuel compatable engine. Check it out.


GM's L83 is advertised as E85 compatible.

The




The topic of discussion is Ecoboost engines which are direct injected. The L83 is direct injected engine and the new ones are E85 compatible engine yes. On this one I stand corrected.

Aftermarket companies are currently struggling to increase performance in direct injected engines. There are no aftermarket HPFP, no aftermarket injectors to help fuel increased fuel delivery. Tuning is a struggle. It’s apparent there’s many here who don’t understand the design of modern direct injected fuel systems. They are so very similar to high pressure common rail diesel systems that share many of the same issues tuning and failures.
 
Last edited:
Lingenfelter performance offers E85 kits for the L83. LT1 that includes a larger HPFP and larger injectors.

The new generation of direct and port injected engines will make this discussion a mute point though. The advancements in fuel systems are really cool. Port and direct injection is the best of both worlds.
 
Last edited:
Status
Not open for further replies.
Back
Top