dump valves?

Submitted by olib123 on

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Hi have just got my YRV turbo and can i say before i continue i love it!!

Just wondering if anyone on here has fitted a blow off valve or dump valve to yrv turbo and if so is it worth while and easy to do.

many thanks

oli

Hi, Although i dont have a

Submitted by Pocketrocket on

Hi,

Although i dont have a YRV Turbo, I do have many years of turbo tuning various cars.

Really, You don't need a dump valve unless:

A: You just like the noise.
B: You are running pretty high boost levels.

Remember that the YRV gearbox, the dump valve wont work until you take your foot off the throttle, dump valves needs engine vacuum (off throttle) to open up the valve.

Personally I prefer the sound of no dump valve and get the flutter noise. On most turbo cars if you fit a cone air filter you then hear the air flutter back over the compressor wheel during gearchanges. Gives that rally car sound a bit like a pigeon! People commonly call it "wastegate chatter" but there is actually nothing happening from the wastegate to make a noise.

All you are hearing is air passing back over the compressor wheel in the opposite direction, harmless unless very big boost pressures are used.

Although i do normally have a dump valve on my cars, I have developed a switchable version so i can turn it on or off from inside the car. So around town it is turned off as it gets annoying.

Quick video here of flutter in a friends old GTxx, no dump valve fitted, just a cone air filter close to turbo.

http://www.youtube.com/watch?v=OVDoqxfPE8I

greddy type s bov

Submitted by flumperboy on

right guys i ive had my bailey on my car for a week or so now, and its flutter dumping, anyone tryed fitting a greddy type s, i noticed today on my colt the bailey was open on idle, and on the yrv its closed, so there is no vacum behind the bov untill its reved to the point where boost is present, then it opens, which is the way the greddy type s need to work as it was open on my colt which put it into limp mode, and it aint good sucking in unfiltered air, anyone tryed this type valve or Similar, i dont like flutter sound,

vid to show how it should sound
http://www.youtube.com/watch?v=K1JlBYNgxsI&feature=related

he having unfilttered air in as its open on idle,
http://www.youtube.com/watch?v=uY2zj6W5TrM