Ford releases fuel numbers for the new F-150

[jejeosborne]

Diesels are a totally different animal. Most do not have a throttle body period, so vacuum conditions are not part of the equation.

I would be very surprised if the ecoboost is producing any boost at cruise, however they are using two very small variable vane units, so I suppose there may be a reason they are.

Again, vacuum does happen at cruise downstream the butterfly valve when lightly loaded. We were discussing the pressure inside the intercooler and it is always positive..... ALWAYS POSITIVE.

 

[KennyG]

That truck is a 2WD, regular cab and loaded with what looks like a lot less than the "1000 lb" load quoted. Properly loaded, I bet it could even fit in a Prius which would be an interesting comparison with a driver like that.

Don't get me wrong, the Dodge is a good truck, but the 2015 Ford is much more innovative. Personally I think Ford should put a diesel option in the F150, not for economy purposes so much, but to attract the diesel diehards.

I've been eager to see a F150 diesel option for a long time also, but not so much now. With diesel continuing to be 30 to 40% more expensive than gasoline and with the Ecoboost torque numbers, I can't see any real market for a light truck diesel. I'm wondering whether the demand for the Dodge small diesel will fade away quickly.

 

[MinnesotaEric]

At idle yes, at cruise it would absolutely be pulling vacuum.

Engines are air pumps. In order for an air pump to pull vacuum, air into the air pump must be restricted. In gasoline engines, the restriction is the throttle plate which is the devise that governs the amount of air let into the engine-air-pump.

As a result of combustion, the metered air allowed into the engine is mixed with fuel and ignited. In the process of burning, the volume of "air" inside the air pump expands. This expansion from burning the air-fuel mixture is out to work to spin the air pump faster. After the expansion of the air charge is completed, the expended air charge is purged out through the exhaust port through of process of compression and scavenging.

The scavenged air charge still retains energy. On turbo applications, this residual energy is used to spin a fan before flowing out through the rest of the exhaust system. The fan the exhaust gases spins is connected to a compressor fan via an axel.

Unless the air filter is overly restrictive, in front of the throttle plate is the entire weight of the atmosphere. But like a turbine engine, on turbo applications, between the air filter and throttle plate is a compressor that compresses the intake charge. As the intake charge is compressed, it heats up and so thoughtful turbo application run the compressed intake charge through a type of "radiator" called an intercooler to cool the compressed intake charge. Thus under normal conditions, so long as the turbo is spinning, the intercooler is always under some type of positive pressure.

Under sudden wide open conditions, where the throttle plates are opened wide at idle or low rpm allowing manifold vacuum into the intake runner before the turbo can spin up and provide positive pressure, understand that manifold vacuum can only "reach up" the intake only so far before being overwhelmed by atmospheric pressure, and due to intake scavenging , the movement of air already in the intake system, we cannot pull manifold vacuum in an intercooler despite the pressure drop between the inlet and outlet typical of air to air intercooler designs.

Please forgive any typos. This is the longest iPhone post I've ever made.

 

[MinnesotaEric]

I've been eager to see a F150 diesel option for a long time also, but not so much now. With diesel continuing to be 30 to 40% more expensive than gasoline and with the Ecoboost torque numbers, I can't see any real market for a light truck diesel. I'm wondering whether the demand for the Dodge small diesel will fade away quickly.

Ford killed the 4.0L Northstar diesel program in f150s several years ago. The engine program continues to this day and is currently being used in the newest UPS fleet trucks. The Ecoboost itself is a 3.1L Mazda diesel block punched out to 3.5L, converted to gasser, and heavily redesigned. If only Ford had move the high pressure injector pump so it could not leak fuel into the engine oil. The new 2.7 Ecoboost is a fresh sheet design that is radically different than the 3.5L

 

[TomSeller]

I've been eager to see a F150 diesel option for a long time also, but not so much now. With diesel continuing to be 30 to 40% more expensive than gasoline and with the Ecoboost torque numbers, I can't see any real market for a light truck diesel. I'm wondering whether the demand for the Dodge small diesel will fade away quickly.

I would agree for all practical reasons given the 2.7 and 3.5 Ecos cost per mile, but there are die hard diesel customers that would buy it based on fuel source alone.

 

[wawajake]

And Canada's diesel fuel costs are at par with gas (and other countries) ..........so it will gain foothold in Canada for sure.....and eventually I bet we will see the USA market of fuel be less biased towards gas and diesel will be more reasonable cost.

 

[jejeosborne]

Engines are air pumps. In order for an air pump to pull vacuum, air into the air pump must be restricted. In gasoline engines, the restriction is the throttle plate which is the devise that governs the amount of air let into the engine-air-pump.

As a result of combustion, the metered air allowed into the engine is mixed with fuel and ignited. In the process of burning, the volume of "air" inside the air pump expands. This expansion from burning the air-fuel mixture is out to work to spin the air pump faster. After the expansion of the air charge is completed, the expended air charge is purged out through the exhaust port through of process of compression and scavenging.

The scavenged air charge still retains energy. On turbo applications, this residual energy is used to spin a fan before flowing out through the rest of the exhaust system. The fan the exhaust gases spins is connected to a compressor fan via an axel.

Unless the air filter is overly restrictive, in front of the throttle plate is the entire weight of the atmosphere. But like a turbine engine, on turbo applications, between the air filter and throttle plate is a compressor that compresses the intake charge. As the intake charge is compressed, it heats up and so thoughtful turbo application run the compressed intake charge through a type of "radiator" called an intercooler to cool the compressed intake charge. Thus under normal conditions, so long as the turbo is spinning, the intercooler is always under some type of positive pressure.

Under sudden wide open conditions, where the throttle plates are opened wide at idle or low rpm allowing manifold vacuum into the intake runner before the turbo can spin up and provide positive pressure, understand that manifold vacuum can only "reach up" the intake only so far before being overwhelmed by atmospheric pressure, and due to intake scavenging , the movement of air already in the intake system, we cannot pull manifold vacuum in an intercooler despite the pressure drop between the inlet and outlet typical of air to air intercooler designs.

Please forgive any typos. This is the longest iPhone post I've ever made.

Thanks for the post.

 

[Paystar]

I only buy new, but for sure now I'd never buy a used Eco-Boom with holes drilled in the intercooler, LOL.

 

[tcartwri]

Thus under normal conditions, so long as the turbo is spinning, the intercooler is always under some type of positive pressure.

Typically at idle a turbo will be free wheeling. In fact you can touch the impeller with your finger and it will stop immediately. On a larger turbo ( basically any other application than an ecoboost ) It can take quite a bit of exhaust energy to get it to spin up. So no, you can't just make a blanket statement that all intercoolers will be under pressure at all times.

Again, someone needs to put a gauge on it while they're running down the road rather than just hypothesizing.

 

[dodge man]

Keep in mine when they write up these reviews, such as motor trend, they are subjective. You can try and find all sorts of problems with their numbers, how they cheated etc. but in the end they liked the Ram best. Its clear the Ford had the best performance numbers.

There is now way anything in a half ton is going to compete with the Ecodiesel on fuel mileage this year, its a clear winner in that category. I'm hoping diesel fuel costs drop soon. Its gotten crazy, in my area they dropped along with gas prices but as of today, I saw a place that diesel was $1.20 more a gallon for diesel.