Dump valve/Turbo chatter.

[Andy]

Really depends on the type of valve you've got and where you've taken the vacuum feed from. Yoof has his DV in the same location as you Kieran, but had to fit a weaker spring in it to get it to dump properly. The OEM type Bosch recirc valves generally have very weak springs, so dump very easily.

[youngprodigys]

i have a rather fat hose coming from the turbo to the 3" intercooler - it backs up and cant escape fast from it - ive had a bosch valve on it and it did the same but not as bad as it does with the greddy one. my vacuum is coming from the fuel rail circuit so should be pulling quite well