Does Kubota publish the torgue spec on our tractors ? I think running our tractor at peak torque rpm like I do my diesal pickup when towing would be a good way to operate. Just my thought,
Sort of ... Kubota shows 'perfomance curves' for each engine block, but not for each varient in aspiration, etc.
For example this is the same block as in my B2650, but also in a B2920 ...
www.kubotaengine.com/assets/documents/Brochures.../05-D1305_E4B.pdf
but ...
www.kubotaengine.com/assets/documents/11_d1305_30.pdf
The primary difference in HP is that they apparently have better aspiration on the 29hp version (more fuel+air in) and then hit a higher rpm with correspondingly higher hp. The US B2920 is spec'ed as 29hp@2900rpm, and the B2620 is sped'ed as 26hp@2500rpm - same block, same displacement.
Power (as in horsepower) is work per unit time.
Torque is work per revolution (or radian).
Running at peak HP gets work done in less time (assuming that's possible)
Running at peak Torque gets work done in fewer engine revolutions.
Note that peak HP is always near the engine rpm limits and often spec'd only for intermittent use. Never a good working rpm for continuous tasks..
Frankly, diesel torque curves are so flat, that you have a wide range of RPM where you get near-optimal work per revolution.
