Car Tips: What Is The Blow Off Valve

Car Tips: What Is The Blow off valve

Modified turbine cars often make a "yi-yi-yi-yi" exhaust sound, which is the sound of the Blow Off Valve!

The word "Turbo" has become more common since carmakers began developing small-displacement turboengines in a bid to meet exhaust standards. Although the turbocharged body is the main part of the turbocharging system, it still needs a series of peripheral components to function properly. The Blow Off Valve is one of the most popular parts of a turbocharging system.
This part is often referred to in the modified boundary, mainly because many of the modified pressure release valve can exhaust of the "white", some of the pressure relief valve discharge's voice is very special, in some my ears like the wonderful music pleasing to the ear, even if you have some ways to add gives the voice device. But what is the use of such a device?

In fact, for turbine engines, the pressure relief valve is a very important part, which can play the role of protecting the engine and turbine. Since the turbine blades are driven mainly by exhaust gas, when the speed increases, exhaust gas will enter in large quantities, and the turbine will provide a continuous supply of compressed air to the engine. If you release the throttle, the throttle will close immediately. The problem is that the turbine is still working due to inertia, and the high-pressure air generated will block, causing damage to the turbine blades or throttle due to impact. And the intake pressure relief valve is to release this moment of high pressure air, to protect the turbine and throttle.
Operating principle of internal discharge pressure relief valve

Intake pressure relief valves are mainly divided into two categories: inner exhaust type and outer exhaust type, which are usually installed between the throttle and the intercooler. Because the pressurization value of the original car is generally low, so the original factory will choose the inner row type Blow-Off, its principle is to open the valve body when the throttle is closed, at this time the compressed air will be discharged back to the intake pipe through a pipe. The advantage of this type of pressure relief valve is that the total gas volume of the Air Flow Sensor will not be changed, while the disadvantage is that there may be incomplete pressure relief phenomenon for highly pressurized turbines. No "deflating" sound (lol XD).

The exhaust pressure relief valve is to solve the problem of pressure relief is not complete and emerged at the moment, this kind of pressure relief valve is different in that it directly emits high pressure air into the atmosphere, so there is the "yi yi" exhaust sound. The exhaust pressure relief valve does not have the problem of insufficient pressure relief for the large turbine, but it should be adjusted properly, because if the pressure relief point is adjusted too early, the throttle is not closed when the "premature", will lead to the boost value can not reach the normal level, and cause power loss; If it's too late, you know what happens.

Be worth what carry is, if the modified outside of the valve is installed between the throttle and the air flow meter, discharge valve is likely will be part of the air flow meter has good air discharge, but as a result of ECU panels is according to the calculation of the air flowmeter signal, then can produce fuel injection quantity is not accurate, This modified car friends must pay attention to. Another point is that usually high-horsepower modified cars will use this kind of Blow-Off because the original internal exhaust pressure relief valve can not cope with too high exhaust pressure, so if the original small turbocharged turbine is installed at will this kind of pressure relief valve, it is likely to affect the output performance!