Blow off or BOV is a valve used in turbo or supercharged engines. Its main purpose is to release the excess pressure created between the throttle and the turbine while turbo is still rotating when shifting gears. This results in pressure remaining in the pipeline due to closed throttle valve. By using BOV, this excess compressed air is forcibly removed from the pipeline to produce characteristic sound for BOV and avoid so-called turbo lag.
We usually distinguish valves into two categories, Open and Closed.
There are also BOV valves for Diesel engines, which only works as sound effect while changing gears.
Boost controller allow a simple increase in turbo pressure. Suitable for all turbocharged and supercharged engines (and diesel). Controllers affect the air pressure from the compressor part of the turbo or compressor leading to the wastegate to increase boost.
There are two types of turbo pressure controllers. Mechanical and Electronic.
Mechanical (or manual) controllers offer a wide range of boost pressure settings. They are simply installed (in the cabin or in the engine compartment), they are simple to operate and require only minimal maintenance.
Electronic turbo pressure controllers are much more sophisticated devices that offer many boost settings according to preset values by user. Pressure changes can be made by gear shift, time, speed or by manual switch.
Intercooler is cooling the compressed air coming from the turbocharger. The advantage of this is that cooler air is thicker, therefore the same volume of air has a higher oxygen content which is more flamable. Such cooled air has a positive effect on the combustion process, and among other benefits also increases performance.
There are several types of input and output for intercoolers:
Intercooler is most often placed in the front of the vehicle. For this location we call it FMIC (Front Mounted Intercooler). Other options are SMIC (Side Mounted Intercooler) or TMIC (Top Mounted Intercooler).
Benefits of using a bigger intercooler:
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