v8dave
Platinum Member
Chris has it correct. You want to operate your tractor at an engine speed that is past its torque peak. That way when you need increased load capacity, you'll get it as the engine slows down. This is really noticable in small cars with overdrive transmissions. As soon as you start up an incline, you can't maintain your speed. Additional throttle usually won't help either, you have to down shift to get engine speed past the torque peak and then you will eventually reach equilibrium. But, it is still a faster speed than in top gear.
Under load, tractors are torque driven not horsepower. John Deere and Kubota sell their small Diesel engines for "industrial" use. Both of them govern the motors to a lower speed in tractor use than their rated power range for industrial use. My Kubota engine has an industrial rating to 3,000 RPM, the tractor governed max is 2600 RPM.
I've also noticed that most (but not all) Diesel engines are their most fuel efficient at, or very close to, their torque peak.
Dave
Under load, tractors are torque driven not horsepower. John Deere and Kubota sell their small Diesel engines for "industrial" use. Both of them govern the motors to a lower speed in tractor use than their rated power range for industrial use. My Kubota engine has an industrial rating to 3,000 RPM, the tractor governed max is 2600 RPM.
I've also noticed that most (but not all) Diesel engines are their most fuel efficient at, or very close to, their torque peak.
Dave
