View Full Version : Why fititng an aftermarket Dump Valve
Hello mates! I looked on the htreads but did not find a specific question like this...
1.- Why fitting an aftermarket Dump valve if the turbo already has a built in valve?
2.- BTW turbo presure is controlled with the waste gate and the DV? or just the waste gate.
Thanks as always!!!
side_effex
28-03-2007, 18:42
first off i'm still learning about this to so please correct me if i'm wrong.
1. The original "dump valve" isn't actually a dump valve, it's a recirculating valve. The recirculating valve just recirculates the pressure where as a dump valve dumps the pressure into the atmoshphere.
2. The boost pressure is controlled by an actuator which in turn opens/ closes the wastegate
Hope that's right....
Thank you side effect!
i think that the original is actually a dump valve; I have a picture of the turbo here
http://img251.imageshack.us/img251/5070/parts4rsale002turboqy9.th.jpg (http://img251.imageshack.us/my.php?image=parts4rsale002turboqy9.jpg)
BTW, I have a diagram of the recirculating system of the 1.8t engine founded in VW and Audis... I've heard that system is used to avoid the turbo stalling whrn you close the throttle to change gears (as a DV) and it is also used to control the turbo presure working jointly with a wastegate
http://img507.imageshack.us/img507/4193/vw18tlj4.th.jpg (http://img507.imageshack.us/my.php?image=vw18tlj4.jpg)
people fit a dump valve on these engines for the noise only, they serve no real purpose and cause many running problems
side_effex
29-03-2007, 11:58
they don't serve a purpose as there's one on the standard LET and the LEH so no point in putting another one on there. If you got a Garrett turbo upgrade or something similar then it would serve a purpose as upgrade turbo's don't come with dump valves.
jayz20let
29-03-2007, 15:48
people fit a dump valve on these engines for the noise only, they serve no real purpose and cause many running problems
had my aftermarket dumpvalve fitted for bout 9 months now and absolutly no problems atall,it was rolling roaded when i brought the car in standard form and has been rolling roaded few weeks ago,the power is still just around the same . so now leaks or problems being caused on my car,maybe just isolated cases where problems arise?