Injection system - carburettor. The simplest way to increase power is to replace the jets in your carb. However, using this option, you will not only increase capacity but also the consumption of gasoline.
Another option is to replace the camshaft. In this case, you change the Cam on the shaft with different angles and heights of Cams that will provide a greater amount and duration of opening of valves. This will change the interchange and increase capacity. But there are negative consequences camshaft replacement - increase loads on the valve gear, the valves can start sticking. To avoid this requires the installation of sport (titanium) valve springs. The valves can break off from a sharp rise in the installed camshaft, so you need to replace the valves themselves to reinforced.
A more time consuming option - boring of cylinder head (cylinder head). When boring the cylinder head increases the diameter of the inlet and outlet channels, and set the valves with large diameter plates. Of the downsides of this method are the large depreciation of the timing.
Boring the cylinder block. By choosing this method, you increase displacement and therefore power. The downside of this method is the risk of damage to the engine cooling system. If the cylinder block is made of light alloy metal, there is a possibility of overheating of the motor.
Nitrous oxide N20. This option force the most unreliable and quite expensive. With fuel in the cylinders serves nitrous oxide. This gas, known as laughing used for anesthesia. The principle that under high temperatures the nitrous oxide splits and cylinder gets an additional portion of oxygen, which increases detonation. In this method there is a risk of burning the piston rings and the pistons themselves. Using it is better to replace the pistons rings on reinforced. Also the life of the engine considerably reduced. At the time of injection engine power can be increased 50-80 l.forces.