# Same engine displacement different HP models?



## J_E_F_F (Jul 29, 2020)

In this example from LS tractors, they use what seems to be the same L3C19 motor in 3 versions producing 30, 35, and 40 HP

How do they generally make a modern tractor engine with the same displacement, bore & stroke, RPM, compression on the 30,35 HP models, and even lower the compression on the 40HP model?

Logic tells me they should increase displacement and possibly compression for increased horsepower.

Since there is a change in compression for the 40hp model, it can't be all ECM magic can it?


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## Hoodoo Valley (Nov 14, 2006)

John Deere does that with their 3.0 liter engine as well, but there's actually even a larger range in the hp. Same exact engine.


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## FredM (Nov 18, 2015)

pump settings with increased fuel flow.


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## Ultradog (Feb 27, 2005)

Are they all turboed?
Maybe one is NA?


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## J_E_F_F (Jul 29, 2020)

All non turbo, naturally aspirated


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## Hoodoo Valley (Nov 14, 2006)

I'd think that the smaller hp on the same engine would last longer.


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## J_E_F_F (Jul 29, 2020)

not necessarily, you might work a lower HP engine harder than a higher one.


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## Groo (Jan 17, 2020)

Look at the ford EcoBoost 3.5, 3 or 4 hp level all programming. Outboards are generally 3 hp ratings per basic engine as well.

It is one of the reasons Deere is fighting "right to repair" . They want you to pay for the higher rated machine instead of just having the ecu flashed.


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## Busted Tractor (May 22, 2018)

The MT230 & MT 235 are natural aspirated. The MT 240 is has a turbo. (www.tractordata.com) This also explains why the compression ratio is different. As for the smaller two having different HP ratings probably have different fueling rates. That has been something manufacturers have done often. It helps in development costs and is cheaper to change the fuel rates than make a completely different engine. This is why you can't find a lawn mower with HP stated on them anymore. Now they are rated by gross torque. Probably a neighbor found his engine was the same size but the they were both rated different--Lawsuit.


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## J_E_F_F (Jul 29, 2020)

Thanks @Busted Tractor , interesting, you are correct, they don't make it really clear in the brochure, for the MT2 series they list the motors as 3-CLY CRDI, NA, Water- cooled and 3-CLY CRDI, TC, Water- cooled, which I now see is naturally aspirated and turbo charged. In the other models, they specifically spell out Turbo, as in 3-CLY Turbo, CRDI, Water-cooled. Interesting the way they chose to do that.


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