Dump Valves

What are dump Valves 

Dump valves (a.k.a blow-off valves) are used to release pressure from turbocharged engines. They are fitted between the throttle body and compressor outlet. Cars are fitted with valves to relieve pressure as standard, however many racing and motorsports enthusiasts choose to have dump valves fitted. This is mainly due to their superior performance – and the unmistakable sounds they make!

Dump valves prevent pressure from being forced back into the engine and release the air back into the atmosphere. As this excess pressure is released, a hissing sound is produced, which is music to the ears of many a petrolhead!

How Does a Dump Valve Work 

A dump valve  (also referred to as a blow off valve or compressor bypass valve) is a pressure release system that can be found in the majority of petrol turbocharged engines. A dump valve will reduce pressure in the intake system as the throttle closes, which prevents compressor surge.

When any turbocharged car is on boost, the entire intake system is becomes filled with pressurised air. This starts at the turbo compressor and passes through the throttle body and inlet manifold before finally reaching the combustion chambers. When you close the throttle, this pressurised air is unable to get into the engine.

Instead, it tries to flow backward through the turbo compressor, which it wasn’t designed to do. This backward flow causes a fluttering noise as the air hits the spinning blades of the turbo compressor. The dump valve will use vacuum/pressure signals to let the piston know when to open and close.

What is the Benefit of a Dump Valve

Car manufacturers usually fit dump valves to cars to improve emissions, fuel economy and driveability. However, when they are fitted after the fact the main reasons for installing a Dump Valve is to handle higher-than-normal boost levels, improve throttle response by staying closed when not venting. Another benefit of dump valves is that they help to prevent turbo damage by slowing it when the throttle is closed stopping over speeding which can damage the turbo. 

Does a Dump Valve Increase BHP 

As the main purpose of a dump valve is to release pressure you would only get increased BHP if the current one is leaking. 

Do Dump Valves Work on Diesels 

In some instances dump valves have been successfully installed on a diesel car. However this is a relatively complex process and doesn’t actually benefit the car in any way when it comes to improved performance. The main reason for not fitting dump valves however is that the majority of diesel cars do not have throttle plates or butterflies. 

A Wide Choice of Performance Dump/Blow-off Valves to Suit Your Driving Needs

Here at Compbrake, we stock a range of superior quality dump valves and accessories to help you supercharge your car’s performance. We offer blow-off valves for a wide range of popular car makes and models, in addition to a range of universal valves and drift fuel pressure gauges.  Our dump valves and are the perfect choice for street, rally or circuit cars.

Why Choose Compbrake for your High Quality Dump Valves 

As with all our other products our dump valves and associated accessories are of the highest quality and engineered to deliver first-class driving and racing performance. Our team have extensive experience when it comes to the provision of bespoke specialist parts to motor enthusiasts worldwide. Treat yourself and your car to a high-performance dump valve from Compbrake and you’re sure to notice the difference in performance. You’ll also hear the beautiful hiss that any motorsports fan knows and loves!

We also offer our clients fast and affordable delivery throughout the UK and anywhere else in the world. 

If you have any questions regarding your order or any of the products in the Compbrake range, please call 01744 895888. Or, simply fill in our Online Contact Form and a member of our team will respond to your enquiry as quickly as possible.