Engine Enhancement (valve chamber)

Camshaft
Undisputed, when it comes to lifting the engine revolution range high into the air, must be a high angle camshaft. Maybe some people will not understand, increased valve lift, should not the whole paragraph of the intake and exhaust efficiency will improve it? This involves a concept called volumetric efficiency of the. In simple terms, if you use a straw to drink beverages, "cattle drink" when certainly anxious insert a special pearl milk tea to drink a cup of thick straw go mad breath, go to your M remember the hot coffee straw ah, this But if for some reason you want to drink slowly slowly suck it, higher smaller diameter straw instead draw efficiency, impreza gc8 coilovers which is like we usually drive more commonly low; the situation is like the engine of high speed full load speed low-load conditions. The longer the greater the degree of valve opening on time, and only when the piston velocity fast enough will have a higher intake efficiency (due to intake efficiency is determined by the pressure difference between the inlet and the cylinder, if inflatable too fast, the pressure difference will shrink faster than the air flow rate will slow down). On the other hand, large throttle opening long time, this time to open the intake and exhaust valve overlap, the situation will be exacerbated by the exhaust gas inlet intrusion, while the remaining amount so that the compressed gas cylinder too high, the engine is running at low speed will unstable, which is why most of the high turn racing engine idling to be a reason for its high ratio of civilian engine (the other main reason is their link crank and flywheel systems are very light, rotational inertia is small, only when the high-speed rotation can maintain a steady speed). High angle camshaft what effect? See below. Note, however, that for turbocharged engines, the intake camshaft efficiency of each section, and the turbine to the amount of wind speed at each match, if already in the turbine area of ​​weakness increased camshaft opening angle is equal futile, but at its best when the turbine was upon her throat, wasted energy is pressurized. So large turbo modification, even if the maximum engine speed does not lift too much, in most cases the proposed replacement of the high angle of the camshaft to match the high output characteristic turn large turbines.

After the replacement of the high angle of the camshaft, this may indicate that the level of horsepower FIG exactly the characteristics of the camshaft angle. The blue line is 272 °, the red line is 264 °, the opening of smaller and more powerful low rpm camshaft (6500rpm or less victory), and the high angle camshaft is the last paragraph of the explosive stronger (8000rpm later). STI Coilovers
Similarly camshaft angle (280 °), the blue line is a low-charged, the red line is high supercharging, the abscissa is the engine speed. You can see at low boost the value, the engine has plenty of torque very plain, which is at a higher intake efficiency, horsepower straight up, then the high efficiency of the camshaft, but not fully utilize the potential of the camshaft ; high torque boost will see fall in the higher speed zone (8000rpm) to indicate intake efficiency began to fall, to limit camshaft (but the engine speed reaches 9500rpm).