Forgive my ignorance. I was just wondering what a dump valve actually does.... I know (think) it can only be fitted to a car with a turbo and it makes a nice little "blowoff" sound after a lot of throttle, but what does it actually do to the engine which gives it more performance?
Dump Valves
- Thread starter FrannoBaz
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When the turbo spins up it creates positive pressure or boost. When the throttle is open the boost goes into the engine and everything is hunkydory. When the throttle is closed (changing gear or backing off) the boost as nowhere to go, which in turns makes the turbo stall. To prevent the turbo from stalling the DV opens to release the built up boost, thus keeping the turbo spinning. This has a few benifits including less time taken for the turbo to spin upto speed and it also helps keep the turbo healthy. When the turbo stalls the boost is forced back through the compressor blades. This causes the turbo to vibrate and in some cases will damage the tubo. It also makes the sound that people call waste gate chatter. It isnt, just the sound of your turbo taking a battering.
DV haters usually wish they either owned a turbo car or have no clue what the DV does. There are quiet DV's which internally recirculate the boost back into the engine.
Its not all about the sound for many people who have them. Some people prefer to get some decent use out or their turbo.
DV haters usually wish they either owned a turbo car or have no clue what the DV does. There are quiet DV's which internally recirculate the boost back into the engine.
Its not all about the sound for many people who have them. Some people prefer to get some decent use out or their turbo.
When people say dump valve, they are generally referring to a blow off valve as that has the stereotypical fast and the furious sound.
They are essentially a pressure release system, intended to prevent compressor surge. When your turbo is spooling and you close the throttle, e.g. when changing gears, the turbo obviously has to spin down meaning there is still compressed air trying to enter the engine. This is where the dump valve comes in, either venting the air to the atmosphere (blow-off valve) or re-circulating the air back into the intake (re-circ valve/CBV)
They are essentially a pressure release system, intended to prevent compressor surge. When your turbo is spooling and you close the throttle, e.g. when changing gears, the turbo obviously has to spin down meaning there is still compressed air trying to enter the engine. This is where the dump valve comes in, either venting the air to the atmosphere (blow-off valve) or re-circulating the air back into the intake (re-circ valve/CBV)
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Not as much as it would if you ran 35+PSI through something like a T4 or GT30 etc and snapped the shaft causing massive engine damage which would ultimately lead to an engine rebuild.
Rather be called a fag by an ignorant fool than pay out thousands in engine repair.
not like to running 35psi though and then asking what a dump valve is
factor, driving a people carrier like it is awesome, even seeing it go is just fun.How many cars with stupid loud dump valves fitted do you think run 35+PSI and a T4 turbo?
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Well considering higher boost pressure would equate to more noise I guess maybe a few
That wasn't the point of my post.
What I was reacting to was a generalised, short sighted, ignorant and biased opinion of what using/owning a dump valve equates to.
It was a **** stirring post, and they **** me off to be quite honest.