hello guys.another question from me again,just 5mins ago i started my 2wd saph and on start up my bruv noticed that my bailey dump valve was open and the cars revs wer hunting up and down,its always done this for about 1minuit then it settles down,is the dump valve supposed to be open on start up with no throttle applied?.thankyou

 

mines duz this dude but if u take the vacum pipe of the top of it then it wount do it must just b the vacum in the manifold at start up that causes this, am taken ma dump valve off tho duz ma tits in

 

thanks for that mate,yer i was thinking of taking it off as iv heard a few bad storys of dump valves on cossies,how would i go about taking the dump valve off,what would replace it?
thankyou

 

i hav a blankin plug thing to put in ma hose where the dump valve used to b but not sure where the vacum hose is ment to go,

 

hmm am not sure either,personally i hate the noise of dumpvalves,they get annoying,if i was to take it off would i need the standard dump valve thing what goes on the intake side,thankyou

 

dont no mate a mate of mine took his off and just put a plug in the hose then the vacum pipe went to the amal valve aparently hes runnin his without any dumpvalve or resic valve and all u hear is the wastegate sounds the business

 

My dumpvalve sucks air on idle too but has a filter on it so no harm there. If you lose the dumpvalve you will get turbo stall which is what you are calling wastegate chatter. I wouldn't run a turbo on serious boost without one.
Atmospheric dumpvalves can be annoying on long journeys and commuting, I may try a recirc item next

 

i wil be running a msd stage 3 set up with a t34,what would you reccomend .thankyou mate for your reply

 

All dump valves open when no throttle is applied when throttle is applied it then closes and opens fast when you release causing the thsssssssshhhhhhh lol so it's normal stg3 there is no need for a dv it's purely a personal thing. I like them cos when I was little I used to be amazed by the sound of a cossie or rst with a dv lol again not everyone likes them but I do

 

Mine does when cold as the ISCV opens so I get like a "Whistling Sound" as soon as ISCV closes it stops.

Yes the standard item you refer to is a Bosch recirulating dump valve.

Martin