How do they make several different HP tractors with all the other specs being the same?

mwemaxxowner

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Yes....BUT.....

At load...in theory the 60hp tractor will burn 50% more fuel....because it makes 50% more power
Yes, but that's only if you're asking to use ALL of that power. For example, we all have 300+hp pickup trucks these days.

However, it only takes a finite amount of power to accomplish a given task. If I'm towing 6000 lbs down the road but I'm not at full throttle, I'm not using all 300+ HP. It's not necessary, the task at hand isn't requiring it all. I saw calculations one time about the amount of horsepower required to move x trailer weight up some specific grade at a specific speed, and it was way less than we would have guessed. It was only like 150 HP.

So, my point, if you were to do the exact same task as the 40 HP tractor with the 60. Same speed, same ground, same implement, obviously the task only requires 40 HP or less. So you're not going to be using all 60 HP. Thus only using 40 HP worth of fuel.

Back to the truck comparison. This is why I get 20 mpg unloaded but 10 mpg towing. While towing the task requires more horsepower. And towing in the mountains even more. And occasionally might have the foot in the floor actually using all 300+ HP and the instantaneous mileage screen shows something like 1 mpg.

At any given time we're only using as much horsepower as we're demanding from the machine. Not necessarily what it has as a maximum. There would be a direct correlation to fuel used at specific horsepower demands.

Obviously this is an oversimplification to try to make it easy to discuss a point, but I believe what I have stated is (at least loosely) true. There are other variables of course.

I would say buy the 60 HP tractor. Running it at partial throttle accomplishes about the same thing fuel wise as them neutering the same engine electronically via tuning.
 
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ericm979

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The larger engine has greater friction and pumping losses (i.e. windage in the crankcase). It's pumping more engine oil and may be pumping more hydraulic fluid too if the pump is larger than the one on the derated model.

Also keep in mind that in a diesel there is no throttle, the max amount of air is always going through the engine. That's got to be pumped in and out too. So the larger engine is doing more dead work there too.

Of course this is not an issue if the two models use the same engine with just injection system changes to make more power on one model. The more powerful model may weigh more in either case, which would increase it's consumption some.
 

LouNY

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If you would like to see a set of tractors that are pretty much identical except for horsepower,
go to tractor data .com and look at the CIH 7210, 7220, 7230, 7240, and 7250 these all use the Cummins 8.3 engine and usually 18 speed power shift transmission the HP starts at 130HP and goes up to 215HP claimed at the pto.
TractorData.com CaseIH 7210 tractor information

These tractors are mechanical injected turbo charged 6 cylinder 8.3 Liter diesels with an 85 HP spread from the lower model to the higher.
As far as the comments on fuel usage the differences are not a major issue when they are doing the same work.
Also many of the smaller and mid range models have been turned up a bit to be closer to the higher HP models,
I almost said bigger but they are mostly the same size tractors, the 7210 did have only 3 1/2" diameter rear axle shafts,
while the rest have 4" axle shafts.
 

MechanicalGuy

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The larger engine has greater friction and pumping losses (i.e. windage in the crankcase). It's pumping more engine oil and may be pumping more hydraulic fluid too if the pump is larger than the one on the derated model.

Also keep in mind that in a diesel there is no throttle, the max amount of air is always going through the engine. That's got to be pumped in and out too. So the larger engine is doing more dead work there too.

Of course this is not an issue if the two models use the same engine with just injection system changes to make more power on one model. The more powerful model may weigh more in either case, which would increase it's consumption some.
It's not a larger engine, that's what this whole thread is talking about.

I think it got off track, because I think the original poster was talking about different horsepower engines turning the same size hydraulic pumps.
 

Anakist

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I found when looking at info on the shibaura engines in the New Hollands, that the 40, 45, and 50, are all the "same" engine.

The 45hp has a stroked crank, and the 50hp has a turbo, but it is the same block and nearly everything else.

Some of that is model creep, the 40 gets updated to a 45 because everything gets bigger every model refresh, but some is having different hp and fuel usage for different costs.

James
 

rademamj1

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Tuning does play an important part of why the same diesel engine platform has three HP models. Normally I don't consider adding a turbo as part of tuning, but my son sure disagreed with me. And he was quick to clarify that most tuning benefits increase horsepower rating with long term engine reliability encouraged. It's a cost benefit marketing decision, and it's done by every tractor manufacturer.
 

Hay Dude

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If you would like to see a set of tractors that are pretty much identical except for horsepower,
go to tractor data .com and look at the CIH 7210, 7220, 7230, 7240, and 7250 these all use the Cummins 8.3 engine and usually 18 speed power shift transmission the HP starts at 130HP and goes up to 215HP claimed at the pto.
TractorData.com CaseIH 7210 tractor information

These tractors are mechanical injected turbo charged 6 cylinder 8.3 Liter diesels with an 85 HP spread from the lower model to the higher.
As far as the comments on fuel usage the differences are not a major issue when they are doing the same work.
Also many of the smaller and mid range models have been turned up a bit to be closer to the higher HP models,
I almost said bigger but they are mostly the same size tractors, the 7210 did have only 3 1/2" diameter rear axle shafts,
while the rest have 4" axle shafts.
I have the successor to that line of tractors, an MX-270. The 8.3L Cummins (CDC) pulls a 12 ton Hesston large square baler perfectly. I will be running that tractor & baler in about 4 hours :giggle:
Its got stupid power and a really nice turbo whistle. We dynoed it earlier this year and it made 270HP at the PTO.

1623927025103.png


New Holland Genesis tractors had a similar iineup. The 70 series utilized the same Ford/New Holland 7.5L diesel from 170-240HP.
Sometimes in other tractor series, the lower powered models of the lineup will not be intercooled Or may not be turbocharged (NA) along with lower fueling from the pump.
 

mred2

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LS 4145XR, LS4150XR and LS 4155XR, same engine, same part numbers, same turbo, same ECU, but different ECU programming. Will the 4145 outlive the 4155 when both are run the same? I don't think so, as most of these are less than 250 hours a year. But when mowing, 10 hp makes a difference.
Agree most is marketing.
 

MechanicalGuy

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Nope, the engine and all its components. Put in a bigger injector and it’s not the same.
The mx series that I listed are the same engines. Injectors and all. Tuning is the only difference, that's what his question was, so explained it.
 
 
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