Why no Ecoboost in the F250?

[Renze]

The straight 6 of the same displacement usually has a longer stroke.
Longer crank arms = more leverage = more torque at lower RPMs.

It's all very interesting the balance between torque, HP, and what RPMs you want them to develop at per the intended application.

Actually, when you calculate the same piston pressure in engines with identical swept volume irregardless of the bore and stroke ratio, you calculate identical torque

The horsemans tale that long stroke engines had better low end torque, is true, however it has no relation to the crank length: It is because long stroke engines have a smaller bore to achieve the same swept volume as a short stroke engine. But in the head of the smaller bore long stroke engine there is less room for intake valves and channels, so the long stroke engine cant fill its cylinders as good as a big bore engine: they get better cylinder fill at lower rpm where air speed in intake channels reaches a speed that the moving air mass, compresses the content of the cylinder a bit when the piston is at bottom dead center and the inlet valve is about to close.

In some high end engines, designers design the intake runners specifically to make use of the dynamic charging effect, to tune theit engines fill grade for a certain power band, or even use variable length intake runners

Dynamic Charging

 

[Hay Dude]

People dont trust them because they expect they are designed the same way as the Oldsmobile 88 Diesel: Olds took a gasser, put different heads and pistons in it to double the compression ratio, even though the number and size of headbolts remained the same.

I suppose people assume Ecoboosts are designed the same way: As atmospheric engine designs with a turbo slapped on and thats it. I assume not, because they werent developed in a rush under an ongoing oil crisis, but i can understand why people want to see before they believe...

I mean, Fendt had a 6.1 liter twin turbo Deutz engine in their 280hp 828 model, and they introduced its successor, the 728, with 300hp from a 7.5 liter Agco (Sisu, Valmet) engine governed at max 1700rpm... the 6.1 Deutz was often toast within 5000hrs of severe duty... So they now went back to an engine with 20% more displacement, but 20% lower top rpm, and a single, fixed geometry turbo...

So even in heavy duty engines, they seem to be getting back from the whole downsizing thing, they now try to gain efficiency by running it at a lower rpm (though still at 40hp per liter)

I always stay away from tractors with small displacement engines making abnormally high power numbers.
The only thing that concerns me about my Massey 7495 with a 6.6L Sisu is the next model size up had an ~8L Valmet. However, I think 6.6L Sisu has enough displacement to get the job done and last a long time. The bigger Massey was a bit too much tractor.

 

[Redlands Okie]

Actually, when you have the same cylinder pressure in engines with identical swept volume, you get identical torque.

The horsemans tale that long stroke engines had better low end torque, is true, however it has no relation to the crank length: It is because long stroke engines have a smaller bore to achieve the same swept volume as a short stroke engine. But in the head of the smaller bore long stroke engine there is less room for intake valves and channels, so the long stroke engine cant fill its cylinders as good as a big bore engine: they get better cylinder fill at lower rpm where air speed in intake channels reaches a speed that the moving air mass, compresses the content of the cylinder a bit when the piston is at bottom dead center and the inlet valve is about to close.

Interesting info and makes sense. Neat

 

[Renze]

I always stay away from tractors with small displacement engines making abnormally high power numbers.
The only thing that concerns me about my Massey 7495 with a 6.6L Sisu is the next model size up had an 8L Valmet. However, I think 6.6L Sisu has enough displacement to get the job done and last a long time. The bigger Massey was a bit too much tractor.

Yeah, the 7495 had the 6.6 as and the 7497 and 99 had the 7.4 which is a bored and stroked version of the same block.
Nonetheless, the Sisu engine, despite their thirsty and noisy reputation before Agco started investing in them, have allways been solid and reliable, but nowadays they are lean and smooth too, which puts them on top of the range. When Agco had MF use the Vario transmission, they promised that Fendt would keep a German engine. However, now the twin turbo Deutz engines in the 800 series made Fendt customers buy the red Agco model because it had the same Vario but the better engine, they had the Finns build a Fendt version of the 7.4, probably with a 109mm instead of a 108mm bore (which would put it at a round 7.5 liter) to keep both the customers as well as their group accountants happy...

 

[Renze]

If you get an aftermarket tune to add 50-80 HP to a 3.5L ecoboost, the cylinder pressures are getting right up into diesel engine territory though! And they seem to hold up just fine when tuned. I've been saving up my pennies to move into a late-model fully-spec'd 3.5L ecoboost F150 w/ 10-spd myself, but still have sticker shock and love my trusty ol' 2500HD.

A new Duramax or Scorpion is in the ~160-170 bar PCP (peak cylinder pressure) range.

But the 12.8L daimler or Volvo 11L I-6 semi truck motors are more like 220-240 bar PCP at rated power. Measuring this directly is a part of my job which I enjoy quite a bit here in the dyno lab.

So, youre first telling the Ecoboost cylinder pressure is in Diesel territory, and then throw numbers around of a Duramax and a Scorpion, both with a compression ratio of about 17:1
An Ecoboost in high performance trim with 660hp, has a 10 to 1 static compression ratio, and a peak torque of 550ft-lb at 5900rpm.

The Scorpion has a peak torque of 1050lb-ft at 1600rpm.

So when we put things in perspective and divide the torque by the RPM to get an broad index (which is close enough to make my point) the diesels get .65 ft/lb per rpm, and the ecoboost gets to .09 ft lb per revolution. Even if you factor in that the Ecoboost delivers that with half the displacement, the index number doubles, but is still far away from the Scorpion. This is just a broad ballpark calculation of how far the engines are apart in the amount of air pumped into them in order to generate power. And then we still havent factored in static compression ratio.

So, nope: the EcoBoost is still very, very far away from the cylinder fill grades, compression end temperatures, and peak combustion pressures of modern diesels, whether light duty V8s or heavy duty onroad or offroad engines. Diesel cycle and Otto cycle engines still really arent in the same league.

 

[Hay Dude]

Yeah, the 7495 had the 6.6 as and the 7497 and 99 had the 7.4 which is a bored and stroked version of the same block.
Nonetheless, the Sisu engine, despite their thirsty and noisy reputation before Agco started investing in them, have allways been solid and reliable, but nowadays they are lean and smooth too, which puts them on top of the range. When Agco had MF use the Vario transmission, they promised that Fendt would keep a German engine. However, now the twin turbo Deutz engines in the 800 series made Fendt customers buy the red Agco model because it had the same Vario but the better engine, they had the Finns build a Fendt version of the 7.4, probably with a 109mm instead of a 108mm bore (which would put it at a round 7.5 liter) to keep both the customers as well as their group accountants happy...

I feel like the AGCO (Massey/AGCO/Challengers) with the Vario transmissions and 6.6 SISU, 6.6 CAT/Perkins Acert, or the 6.7L Cummins engines are GREAT choices and great VALUE for a used 120-190HP tractor.
I can get one with 4500-6000 hours equipped with a loader for $50-60,000, which is what guys are paying for a new 50HP tractor. It will have a huge cab, most have front suspension and 34MPH road speed, nice operator seat, acceptable buddy seat, locking front & rear diffs, 540E PTO and a lot more.
Great mix of American & European engineering!
Have 2 now and looking for a 3rd to replace my Kubota M126X.

Perfect medium-large haying tractors.

 

[deerefan]

I feel like the AGCO (Massey/AGCO/Challengers) with the Vario transmissions and 6.6 SISU, 6.6 CAT/Perkins Acert, or the 6.7L Cummins engines are GREAT choices and great VALUE for a used 120-190HP tractor.
I can get one with 4500-6000 hours equipped with a loader for $50-60,000, which is what guys are paying for a new 50HP tractor. It will have a huge cab, most have front suspension and 34MPH road speed, nice operator seat, acceptable buddy seat, locking front & rear diffs, 540E PTO and a lot more.
Great mix of American & European engineering!
Have 2 now and looking for a 3rd to replace my Kubota M126X.

Perfect medium-large haying tractors.

In my area, cattle farmers and hay operations are scooping up 20 series (3020-5020) John Deere and the 40 series (4440 and up), overhauling them and putting them to work. They say overall it is cheaper and easier to work on. We have a 2005 John Deere 5103 on our small farm. Great simple machine

 

[5030]

My philosophy with tractors and implements is... 'The more junk in the trunk' (accessories, bells and whistles), the more stuff to fail and cause expensive repairs.

 

[5030]

Just watched the TFL guys take a Ford electric Lightening pickup truck to the top of Alaska. Was interesting in as much as after Fairbanks there are no charging stations. Their chase pickup was a Ford 150 Power Boost EV and they had to charge the electric one from the gas powered EV one and towards the end of the trip to make it. they had to drive under 35 and no climate control in the cab whatsoever. The climate control was sucking too much power.

The only thing that video showed me, besides the fact that EV's aren't ready for prime time yet was the humor of watching them suffer through it. I'll never own one, not interested.

Keep wondering how LE will cope with an EV when they run climate control constantly. I can see a lot of 'dead in the water' cop cars coming. The departments will probably have portable gasoline powered generators to go 'rescue' them... I find the whole thing somewhat humorous and sad at the same time.

Barney fife sitting all day with the AC on and has a speeder pass him and turns on the lights and siren, steps on the fuel pedal and there is nothing.. duh.

 

[Hay Dude]

In my area, cattle farmers and hay operations are scooping up 20 series (3020-5020) John Deere and the 40 series (4440 and up), overhauling them and putting them to work. They say overall it is cheaper and easier to work on. We have a 2005 John Deere 5103 on our small farm. Great simple machine

Those are great tractors and very simple to work on. I have to admit, I like my creature comforts more than those tractors can deliver. I like suspensions and road speed the “newer, old tractors” deliver.
I’m a big believer in CVT transmissions now, too. I thought power shifts were nice, CVT’s blow your mind.

Anyway, back to lightweight gas-turbo engines lol