The need for speed for most drivers has wanted them to ?turbo charge? their cars. So, like in the film Fast and Furious, they're supercharging it up where it's not illegal and they're having a brilliant time unless they have forgotten to look after their turbocharged engines. Without this nifty gadget called dump valves their turbochargers are prone to damage. That works well with petrol-infused cars. How about turbo diesel dump valves?



First, let's see what a dump valve does. A dump valve functions as the absorber and of extremely high pressure, which it releases to the atmosphere or back to the inlet. It's the bypass valve that looks after the car's turbo from taking so much pressure than it can handle.

When the car is in full throttle, it creates pressure known as boost. When the driver suddenly decelerates, the throttle butterfly closes and air gets compressed but there is no other escape route. The unused boost then goes back up through the intercooler, creating pressure at the rear of the turbo. This pressure acts as a brake on the turbo and tries to prevent it from spinning.

How does it perform its purpose? The dump valve will be the leeway, the fire exit if you want to put it that way. It releases the pressure in two ways: into the air outside or back to the air intake system.

Atmospheric valves dump the extra boost to into the air giving out a ?whoosh? sound that the drivers love. Re-circulating valves dumps back the unused boost with no sound at all.

As a result, this modification provides massive decrease in turbo spool up time and there is big improvement in the car's response between changes. Since there is little lag on the turbo, the next boost is quick. This means increased torque at lower RPM.

What about turbo diesel dump valves?

If you are asking if you can use a petrol dump valve in your turbo diesel car, the simple answer is NO. Petrol dump valves are useless to your car because diesel cars are built differently from petrol turbo cars.

Turbo diesel cars are not equipped with the same throttle plates as in a petrol turbo car that control the engine speed. In a diesel car, the engine needs all the air that the turbo charger can give it. It thrives on compressed air for its cylinders to function optimally. A diesel dump valve will only provide the sound but no additional speed.

Diesel dump valves therefore, are not really required because your turbo diesel car loves the high pressure build up. Should you insist on installing a diesel dump valve in your turbo diesel car, you only get the 'woosh' sound when you shift gears.

There isn't much point in arguing about the need of the dump valves in a turbo diesel car. You could fit them if you want the performance sound but ultimately, it's down to individual choice and preference as not everyone who drives a turbo diesel wants to install a dump valve. Some may even find the sound to be repulsive!