How to modify the secondary air inlet?

Secondary air intake means that, in addition to the original air inhaled by the air filter, an air intake device is connected from the PCV (Crankcase Forced Ventilation) pipeline of the engine by using the vacuum pressure difference of the intake manifold, and an appropriate amount of fresh air is introduced to achieve the purpose of improving volumetric efficiency. The modification method is as follows:

1) Remove the positive crankcase ventilation hose.

The function of PCV hose is to make the exhaust gas of the engine return to the engine for re-combustion after filtration and concentration, so as to reduce the exhaust pollution of the engine. Because the exhaust gas contains lubricating oil components that can't be burned in the engine, and engine oil will cause carbon deposition, some vehicles have installed lubricating oil respirators here to filter the lubricating oil. When the engine speed is low, the air is blocked by the throttle. When the engine sucks in air, the negative pressure value of PCV hose is large. When the engine speed is high, at this time, because the throttle valve is fully opened, the negative pressure is relatively reduced, and the intake air volume will be reduced, which will further reduce the relative amount of gas in the secondary intake, which is also the reason why the secondary intake effect is better at low speed than at high speed. When reinstalling, first remove the PCV hose.

2) manufacturing a secondary air inlet pipeline

(1) Cut off the PCV hose of the original vehicle.

(2) Connect a T-street.

(3) Connect the cold air hose at the other two joints of the tee.

(4) Connect the other end of the long cold air hose to the mushroom head filter.

3) Installation

After making the secondary intake pipe, install it on the vehicle.

4) Trial operation

It is considered that the power improvement effect of the secondary intake can be concentrated in the low-speed area by checking the secondary intake effect at low speed. At low speed, the air is blocked by the throttle valve, which makes the intake manifold generate negative pressure. At this time, the secondary intake will use this pressure to suck in excess air, which is the main reason for prompting power. However, after speeding up, the throttle will be fully opened, on the one hand, air will not be restricted and will not enter. On the other hand, when a large amount of air enters and the vacuum degree decreases, the amount of air that can be introduced by the secondary air intake device becomes insignificant compared with the air intake of the trachea.

5) Precautions

When the air intake system is reformed (especially on a large scale), the cooperation with the oil supply system must be considered. If only the air intake capacity is greatly enhanced, and the oil supply system cannot provide enough oil supply to match it, then the purpose of improving power will certainly not be achieved, because the engine needs an appropriate proportion of oil and gas instead of just a large amount of air. The secondary air inlet is an additional air inlet, which is not within the detection range of the air flowmeter. But the engine does not only depend on the air flow meter to determine the fuel injection quantity, and the electronic control of the automobile is digital. Therefore, adjusting a small amount of extra air intake can avoid engine detection and achieve the effect of fuel saving and acceleration. However, once the air intake exceeds the detection sensitivity, the computer will correct it, and sometimes it will be over-corrected, and its fuel saving effect will be worse than that without changing it. Excessive air intake adjustment of secondary air intake will cause unstable idle speed, unsatisfactory acceleration and increased fuel consumption.