Forum Discussion

Lessmore's avatar
Lessmore
Explorer II
Oct 28, 2014

Turbo small displacement - displacement on demand- a winner?

Boy Ford's new 2.7 liter turbo truck engine....375 HP out of 2.7 liters(Correction....325 HP -** Thanks Fast Mopar.).....that's about 168 cubic inches. I did the conversion in my head....so that's just an approximate...I'm sure I'm out a few cubes ...+/-.

The correct cubic inches is 168.** Thanks ib516,

That's an awful lot of power being squeezed out of a relatively tiny engine....in a heavy truck that has a significant payload and towing capacity.

I think somewhere there has to be a balance...between cubic capacity....HP/torque being produced...purpose of the HP/torque.....general durability and long term longevity of certain high stress components. In this case the...high rpm, bearing cooling, capacity of the turbocharger(s).

I'm not a mechanical engineer and I'm sure Ford would have these questions resolved, before production.

But they are things that I would have in the back of my mind, if I owned a 2.7 turbo engine in a truck.

Another question is how low....cubic inch capacity....truck duty....will Ford go ?

They started with the 3.5 turbo V6 in the F 150. Now a 2.7 liter turbo V6 in an F 150 and this 2.7 puts out more HP/Torque than the original 3.5 Truck turbo V6.

How small an engine can Ford go to, in a full sized truck, with full size cargo/tow ratings ?

Where is the bottom line...for cubic inches ?

I'm not being critical, just inquiring.

GM seems to be going with larger cubic capacity, more cylinders...ie; 5.3 liter regularly aspirated (no turbo forced induction)... but with displacement on demand with 6 to 8 cylinders....than cutting out 2 to 4 cylinders under light load.

Which is better ?

Both Ford and GM are looking at the same way of achieving efficiency / improved fuel economy, while maintaining very good HP/Torque output. Same way being with reduced displacement....either permanent (fixed engine capacity, but forced induction- Ford) or varying displacement (displacement on demand, non forced induction- GM).

As with most things, eventually and probably....only one technology will win out.

Which will it be and why ?
Tow Vehicles
  • buddyIam's avatar
    buddyIam
    Explorer
    Oct 28, 2014
    2.7 eco boost is 16.6/21.5/18.5
    5.3 is 13/19/15.2 This is a steel bodied truck
    3.5 Eco is 15/21/17 I believe this is a steel body figure.
    3.7 ford gas is 16/21/18 I believe this and 3.5 eco numbers are with steel body last years model.

    Ram Eco diesel is 18.6/25.8/21.2


    It seems that the 3.5 eco boost might be the sweet spot for Power vs. economy. It takes a precise amount of fuel to make HP. It may be that at 3.5 liter you start to find much smaller gain by reducing cubic inches. When both engines are in the same truck at the same weight.
  • ScottG's avatar
    ScottG
    Nomad
    Oct 28, 2014
    They have a looooong way to go. Even the latest engines are under 35% efficient.
    So there's a lot more power hiding in every gallon of fuel.
  • hone_eagle's avatar
    hone_eagle
    Explorer
    Oct 28, 2014
    ScottG wrote:
    They have a looooong way to go. Even the latest engines are under 35% efficient.
    So there's a lot more power hiding in every gallon of fuel.


    Yes and the weight reduction 'wars' have just begun,how far will that battle go?

    win for the consumers.
  • buddyIam's avatar
    buddyIam
    Explorer
    Oct 28, 2014
    Scott and hone.

    That might be true in the future. But I would think any improvements in efficiency and weight loss is going to apply to both the 2.7 and the 3.5.

    Improvements in efficiency can't change the fundamental laws of physics. At one hundred percent efficiency a gallon of gas will only drive the f 150 so far. And It may be that 3.5 liters may be the sweet spot.

    A steel body 3.5 is just 1 mpg behind the aluminum 2.7. If the aluminum body does indeed save the mpg claimed. Comparing the numbers, it looks as if the 2.7 is not as good a value as the 3.5.
  • 8iron's avatar
    8iron
    Explorer
    Oct 28, 2014
    buddyIam wrote:
    Scott and hone.

    That might be true in the future. But I would think any improvements in efficiency and weight loss is going to apply to both the 2.7 and the 3.5.

    Improvements in efficiency can't change the fundamental laws of physics. At one hundred percent efficiency a gallon of gas will only drive the f 150 so far. And It may be that 3.5 liters may be the sweet spot.

    A steel body 3.5 is just 1 mpg behind the aluminum 2.7. If the aluminum body does indeed save the mpg claimed. Comparing the numbers, it looks as if the 2.7 is not as good a value as the 3.5.


    The 2.7 mpg numbers where "as tested" while the 3.5 mpg numbers were from EPA estimates. I don't think you can use them as a comparison unless both were being tested side by side by the same testing organization.
  • buddyIam's avatar
    buddyIam
    Explorer
    Oct 28, 2014
    The 2.7 was a aluminum body. The 3.5 is a steel body. So they aren't apples to apples for sure. But Motor Trend said the work was done by a emissions expert.

    And except for towing MPG. Most 3.5 owners on this forum claim to be getting at or better MPG than EPA numbers.

    I know I seem a little harsh on the 2.7. But Ford is trying to sell it on MPG and HP. In reality even the 3.5 isn't really good at both while towing. I see no reason why the 2.7 would do any better at towing.

    Some would say it isn't going to be sold for it's towing ability. But you don't need 300 HP for driving around town. If your driving around town the lower priced 3.7 in a steel body which has apx. same MPG as the 2.7 aluminum body, would be the logical choice.

    I guess one could say that the 2.7 is going to be marketed as a replacement for the 3.5 and the 3.7. But I find that hard to believe.
  • Perrysburg_Dodg's avatar
    Perrysburg_Dodg
    Explorer
    Oct 28, 2014
    hone eagle wrote:
    ScottG wrote:
    They have a looooong way to go. Even the latest engines are under 35% efficient.
    So there's a lot more power hiding in every gallon of fuel.


    Yes and the weight reduction 'wars' have just begun,how far will that battle go?

    win for the consumers.


    No win for the average consumers, unless you think $52,000 for a pick up is a win. Most consumers can't afford one of those trucks.

    Don
  • DaveF-250SD's avatar
    DaveF-250SD
    Explorer
    Oct 28, 2014
    I believe the 2.7 will be marketed toward and purchased mostly by folks who don't do much, if any, towing. Mall crawler/street cruising, as well as occasional hauling a half ton of sod or gravel for home improvement projects will be it's main purpose. Likely most will be two wheel drive standard cab short bed models. They may be given a huge tow rating, but duty-cycle wise, they probably will not hold up as well in heavy duty use as the larger displacement offerings. Nor would they be expected to.
  • hone_eagle's avatar
    hone_eagle
    Explorer
    Oct 28, 2014
    Perrysburg Dodgeboy wrote:
    hone eagle wrote:
    ScottG wrote:
    They have a looooong way to go. Even the latest engines are under 35% efficient.
    So there's a lot more power hiding in every gallon of fuel.


    Yes and the weight reduction 'wars' have just begun,how far will that battle go?

    win for the consumers.


    No win for the average consumers, unless you think $52,000 for a pick up is a win. Most consumers can't afford one of those trucks.

    Don


    Cheap for a Canadian, ran into a guy this summer claimed his new Dodge Laramie cost over $90,000 tax in.
  • spoon059's avatar
    spoon059
    Explorer II
    Oct 28, 2014
    hone eagle wrote:
    Yes and the weight reduction 'wars' have just begun,how far will that battle go?

    win for the consumers.

    Win for consumers, potentially a lose for people that tow. The push for greater fuel economy could potentially push manufacturers away from engines that have sufficient power to tow. I like the idea of the Ecoboost engine in the half ton where most miles are empty and you want economy, but some miles are towing and you need power. As the engines get smaller and smaller, I question the longer term reliability of these engines.

    As Don stated also, the cost is exceptionally higher for these engines too. I think its because Ford is only offering the Ecoboost with the more expensive trim packages (at least on the Explorer when I looked at it last year).

    The fact that this is the lighter body and only marginally better economy than the 3.5 is odd to me though. Seems that it should get better than 1mpg more.

    Either way, between the Ecoboost and the Ecodiesel, I hope it forces the other manufacturers to develop more fuel efficient, tow capable engines.

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