what are the ways for modern diesel engines to save energy and reduce emissions?
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   Engine Application 
              Truck 
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   Engine Category 
              Weichai 
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   Tags 
          
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| Model | Rated Power/ Speed | Maximum Torque / Speed(N.m/rpm) | Valve Number | Displacement(L) | 
|---|---|---|---|---|
| WP13.500E40 | 368/1900 | 2100/1200-1500 | 4 | 12.54 | 
| WP13.530E40 | 385/1900 | 2220/1200-1500 | 4 | 12.54 | 
| WP13.550E40 | 405/1900 | 2300/1200-1500 | 4 | 12.54 | 
| WP13.500E501 | 368/1900 | 2400/950-1400 | 4 | 12.54 | 
| WP13.530E501 | 385/1900 | 2500/1000-1400 | 4 | 12.54 | 
| WP13.550E501 | 405/1900 | 2550/1000-1400 | 4 | 12.54 | 
| WP13.500E63 | 368/1900 | 2400/(950-1400) | 4 | 12.54 | 
| WP13.530E63 | 390/1900 | 2500/(950-1400) | 4 | 12.54 | 
| WP13.560E63 | 412/1900 | 2550/(950-1400) | 4 | 12.54 |