can anybody tell me make and name plus dealer of the dump valve that sounds like the squeak on a WRC cars?

 

Well IIRC the HKS SSQV sounds similar to the WRC flutter /chirp

 

No, because it's not a valve that's making that noise. WRC cars don't have DV's, and the chirping you hear is air pulsing back past the turbo blades.

If you want your car to make the same sound (and get better throttle response into the bargain), remove the dumpvalve completely and blank off the pipes/flanges that its removal has left.

How long the turbo will last in this state is anybody's guess, but if you want the same sound, that's how you get it.

 

Or with an HKS SSQV......similar sound that is.