m3, for four cylinder engine, 4-1 extractor design give engine more HP at high rpm, b'cause this design is less back presure of exhaust gas, it will also decrease the low rpm torque.
When driving in low rpm, car need amount of back pressure to give engine enought torque to move the car, so the design of the factory spec extractor is very narrow and small, this will give the car better pick up. But 4-1 extractor design is output the gas as soon as posible, so the back presure at low rpm is very low, then the car is hard to pick up at low rpm. Of course, there is a solution to give engine better pick up and better HP, that is 4-2-1 extractor design.
But for kancil is 3 cylinder engine, so there is only have 3-1 extractor design.