what is a tachometer used for

• 2022-01-13

The tachometer is very important , let us see what is a tachometer used for.

Ignition moment: Four cylinder gasoline engine can ensure successful ignition when the speed reaches 80R / min, but in fact, the starting speed of the engine driven by the general starter can reach 120r / min to ensure the ignition quality. Good electric energy output capacity of the battery is the key to engine starting.

Start-up: The speed of the engine at the moment of starting is high, which can generally reach 1200-1500r / min. it may be higher in cold weather. This is true for all EFI vehicles. Because the temperature is low, the on-board computer will order more refueling. First, it is to make the engine run above idle speed so that it will not shut down due to too low speed, and also to warm up the vehicle as soon as possible to reach the working temperature. When the working condition of the engine is slightly stable, the speed will drop to about 800r / min.

Many people think that a hot car in winter needs to wait until the engine speed reaches the idle speed of the whole vehicle. In fact, it is not. As long as the engine idle speed is stable and there is no obvious fluctuation, and the speed drops to about 1000r / min, it can start. Generally, this process only needs to get on the car, fine tune the seat, wipe the front windshield and fasten the seat belt.

Start:When starting at 1500-2000r / min, the starting speed of cold start should not be too high, because the lubricating oil of cold start engine cannot reach the upper part of the engine, and too high speed will cause heavy wear; If it is a hot start, you can use a slightly higher speed, so that you can start powerfully.

Shift: Only for manual gear, it is more appropriate to shift at about 2500 R / min. at this time, the gear switching is often smooth and powerful, and the economy of the engine is better. If you need to accelerate quickly, you can choose to shift at more than 3000 R / min. at this time, the vehicle has superior power.

Turbo: Turbocharging is to drive the rotor to rotate through the high-speed gas from the exhaust pipe, so as to improve the air flow pressure in the intake pipe. Generally, the turbocharging works well at about 1800r / min, the engine power begins to increase significantly, and the low speed basically does not play a role.