What things are usually modified in car modification?

A. Increase the throttle: increase the intake air flow greatly, but without restriction, the engine will knock due to the low fuel-air mixing ratio.

B high compression ratio and light piston: reduce the load of engine crankshaft and connecting rod, and the engine has fast response and stronger explosive force.

C. High-angle camshaft: The valve lift and opening angle are larger, ensuring more combustible mixture to enter the cylinder and smoother exhaust.

D. Main reduction ratio and gear: increasing the main reduction ratio and encrypting the gear ratio of 1 ~ 4 can improve the acceleration of the whole vehicle, but at the expense of reducing the limit speed. Therefore, we can make up for the lost speed by increasing the tail teeth, encrypting the 2 ~ 4 gear ratio and thinning the 5 gear.

E. High-voltage line: Replace the high-resistance fire line of the original car with the low-resistance fire line, so that the energy released by the ignition coil can be transferred to the spark plug to the maximum extent, but beware of flashover, interference and other symptoms. F. Balance bar: connect the shock absorber tower of the vehicle to enhance the rigidity of the vehicle body and prevent the shock absorber and even the vehicle body from being deformed due to intense manipulation.

G. Spark plug: It is an entry method to change the ordinary nickel-copper spark plug with low cost, short service life of 20,000 kilometers, poor high temperature resistance and low ignition energy into an iridium metal spark plug with long service life of100,000 kilometers, high temperature resistance above 2,000℃ and strong ignition ability, but the corresponding cost is higher. Attention should be paid to the selection of heat resistance value. If it is too low, the engine can't accelerate; if it is too high, it will produce carbon deposit. The Japanese temperature of 5 ~ 7 degrees for naturally aspirated vehicles can achieve the purpose of strengthening, and the turbocharged vehicles are better than 7 degrees.

Note: Generally, Japanese spark plugs are increasing with the nominal increase of 5 degrees, 6 degrees and 7 degrees ....., but European spark plugs such as Bosch spark plugs are just the opposite.

H. Various instruments: Due to inaccurate data transmission, the pointer instruments of the original vehicle often cannot meet the requirements of carefully monitoring the working conditions of large modified vehicles and need to be replaced.

1. Fuel control valve: The original oil return valve is generally 2.5 ~ 4 kPa, and the pressure value of different models is different, so it cannot be adjusted. Increasing fuel pressurization can increase oil return pressure, slow down oil leakage, increase injection pressure, and improve injection atomization while increasing injection quantity.

J. Ground wire: By strengthening the ground wire, the interference of all kinds of electrical equipment can be reduced, and the stable operation of power generation and electrical equipment can be ensured.

K. Aerodynamic kit: namely, aerodynamic kit, which usually consists of front air dam, double front wing plates, side skirts, tail edges and tail fins. It can enhance the visual sense of the car body and adjust the direction of air passing through the car body as needed to assist the power. There are three materials to choose from: heavy aluminum alloy, light and brittle cold carbon fiber and light and tough hot carbon fiber, but hot carbon fiber is more common in racing cars because it is extremely expensive.

Computer adjustment of length: modify ECU program to increase fuel supply, delay fuel cut-off time and adjust horsepower output linearity.

Meter (short for meter) Flywheel is light: If the flywheel with balance function is too heavy, it will affect the re-acceleration. Good acceleration response can be obtained by replacing the light flywheel, and the oil-oil separation and cooperation must be more accurate.

Tires and rims: High-performance tires with high flattening rate are more sensitive and less deformed during vehicle steering, thus increasing grip. Compared with the cast aluminum alloy rim with light weight, high hardness and good heat dissipation, the forged alloy rim has lighter weight, higher strength and higher cost.