16 more HP from the same size engine?

[bilrus61]

In the JD 4000 series the 4720 has 56 PTO hp out of the same sized turbocharged engine as the 4320 that has "only" 40 PTO hp. Both engines are turbocharged. The Kubota L5040 has the same displacement and its turbocharged engine puts out 44 PTO hp. I know you can "turn it up" but that seems like a huge jump in horsepower. Nobody else seems to be able to get that kind of horsepower from a engine of that size. How do they get that kind of boost?

 

[RoyJackson]

Just because the engines are the same displacement doesn't mean they're the same engine (although I'd guess they are the same basic engine).
The turbo will add some power. A higher rated turbocharger, the injection pump, camming and other differences (bigger valves, for example) between the engines can account for the differences in horsepower ratings.

Even the testing method can make a difference when it comes to "advertised" horsepower.

 

[radman1]

That practice is very common in the industry. Larger ag tractors may have 50 hp difference between models in the same series using the same engine. On the CUTs it maybe in part due to +/- a turbocharger and computer changes. On most ag tractors it may be an injector difference but usually just a computer setting difference. A dealer could change the computer settings but if discovered, corporate would be extremely unhappy to say the least.

 

[CurlyDave]

20+ years ago I worked on a project in the diesel truck and engine industry.

One of the most interesting things I discovered was that the same engine could be produced in a wide range of horsepower ratings.

For instance, the 855 cubic inch Cummins engine was sold to fleets with a rating in the 180-200 hp class. Increase the fuel injector size and that same engine would put out 350-400 hp, which is what a lot of owner-operators bought. The penalty was a decrease in life and a decrease in fuel economy.

Take that same engine and put in some really big fuel injectors and the military would buy it as a 1000 hp powerplant for Armored Personnel Carriers. The life decreased to about 5000 miles, and fuel "economy" wasn't on the priority list at all.

 

[MikeInEburg]

A friend works for Mack Truck and told me how they control engine horsepower thru software. A truck owner can purchase an engine HP upgrade and the only change is software. HOWEVER, before they'll do an HP upgrade, they first verify that the transmission is capable of handling the increased power. Something for tractor owners thinking these thoughts to consider as well.
Mike

 

[Nuru]

A friend works for Mack Truck and told me how they control engine horsepower thru software. A truck owner can purchase an engine HP upgrade and the only change is software. HOWEVER, before they'll do an HP upgrade, they first verify that the transmission is capable of handling the increased power. Something for tractor owners thinking these thoughts to consider as well.
Mike

Good point, as yes in some cases it is a software mod.

 

[wolc123]

So I guess that means if you want to keep your tractor a long time, you might be better off with the 4120 rather than the 4720. That would also let you keep lots of your money at purchase, and save even more money on fuel. I have had a 4120 for 5 years and never felt a need for more hp. I can run a 6 ft bush hog all day long on 6 gallons of diesel (just did today in fact) and the tractor has never given me a problem.

 

[jenkinsph]

So I guess that means if you want to keep your tractor a long time, you might be better off with the 4120 rather than the 4720. That would also let you keep lots of your money at purchase, and save even more money on fuel. I have had a 4120 for 5 years and never felt a need for more hp. I can run a 6 ft bush hog all day long on 6 gallons of diesel (just did today in fact) and the tractor has never given me a problem.

When you consider that the 4120 through the 4720 are all using a 149 cu in engine with a turbo none of these are working very hard. I think your thoughts are correct to a lesser degree than you may think. When you take a 149 ci motor and start trying to get 100 hp or higher from it it will indeed shorten the life. If you run a 4120 at full output (43hp)and a 4720 at 2/3 of its output for 44hp I don't think you would see much difference in engine life. The difference between the 43hp engine and the 66hp in performance is substancial though. I have the 43hp Yanmar non turbo motor in my 110 and the 60hp turbo in the 4520 and there is a huge diference in the get up and go.

 

[RollingsFarms]

the 179 ci motor in the 5D & 5E series is an even greater difference then that. in it's lowest setting it puts out 45hp but they crank it up to 74hp. heck, I think it was Montana or some tractor company that was using this same engine in their biggest tractor and getting 80 or 88hp(can't remember exact number) from it! my 5203 uses the same engine as the 5D and 5E series but it's only putting out 56hp with a turbo. funny thing is, I can see the turbo with my own eyes under the hood, touch it, stare at it, take a pic of it, but I can't hear it at all. is it that way with the 4020 series too?

 

[sunnyside360]

......... my 5203 uses the same engine as the 5D and 5E series but it's only putting out 56hp with a turbo. funny thing is, I can see the turbo with my own eyes under the hood, touch it, stare at it, take a pic of it, but I can't hear it at all. is it that way with the 4020 series too?

I can't hear the turbo in either my 4320 or 3720 tractors. I have no trouble hearing the turbo on my Kubota M8200 but it uses about twice as much fuel as the two Deeres.