Finally I found out a very good engine which is also available at Shershah easily...
The engine is K6A 660cc (JDM alto) with 40 KW power and it comes with manual tranny as well :P. Specs are below:
<table class="text" border="0"><tbody><tr bgcolor="#ebebeb"><td>Displacement, cc</td><td>658</td></tr> <tr><td>Engine model</td><td>K6A</td></tr> <tr bgcolor="#ebebeb"><td>Max.power (Net), kw(PS)/rpm</td><td>54 ps (39.72 kw) / 6500 rpm</td></tr> <tr><td>Max.torque(Net), N*m(kg*m)/rpm</td><td>6.2 kg*m (60.80 N*m) / 4000 rpm</td></tr> <tr bgcolor="#ebebeb"><td>Power density</td><td>11.67</td></tr> <tr><td>Engine type</td><td>Water coolingserial 3 cylinder DOHC12 valve</td></tr> <tr bgcolor="#ebebeb"><td>Engine information</td><td>
</td></tr> <tr><td>Fuel system</td><td>EPI (electrically controlled gasoline injection)</td></tr> <tr bgcolor="#ebebeb"><td>Turbocharger</td><td>No</td></tr> <tr><td>Fuel type</td><td>Unleaded regular gasoline</td></tr> <tr bgcolor="#ebebeb"><td>LEV system (Low emission vehicle)</td><td>Yes</td></tr> <tr><td>Compression ratio</td><td>10.5</td></tr> <tr bgcolor="#ebebeb"><td>Bore, mm</td><td>68</td></tr> <tr><td>Stroke, mm</td><td>60.4</td></tr> <tr bgcolor="#ebebeb"><td>Final gear ratio</td><td>
</td></tr> <tr><td>Fuel consumption at 10-15 modes, l/100km</td><td>4.3</td></tr> <tr bgcolor="#ebebeb"><td>Fuel consumption at 60 km/h, l/100km</td><td>
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