Right, this im sure would have been asked a thousand times, but thanks to a new housing estate i only have dial up and would take me at least 6 days to find what i want

Anyway, WHAT are the true traits of running dumpvalves? My S2 had it mainly cos i liked it and not worried about air leak or reliability issues etc

I have read that you only need a dv if your running over 250 bhp. Is thsi true? My saph runs 330bhp and has a dv. Is it safe to runit without one?

AND if it is ok, then why have dv in first place?? Tad confused here, so if Stu/Rainbird or anyone else PLEASE explain it be appreciated.

Thanks

 

No I would not fit one under any circumstances unless the engine spec dicated I needed one.

I hate the bloody things.

 

I'd run one on any roller bearing turbo application or anything over 2 bar of boost

 

As above,NEVER

 

Burn them all

 

Don't some of the GT Garett turbos need to run one though?

 

Took mine OFF, really got on my nerves

 

answer is...when ur gay....

 

Answer is:

GT Series turbos should have them fitted

T4 and above turbos need them

According to Vince, who used to work at Universal Turbos at least....

I have had both T34 and T38 Turbos running over 30 psi with no DV as I personally hate the noise. Now I have a T4, I will be using a DV.

Si

 

Roller bearing turbo shafts do suffer on high boost applications without one.

I'm running a Tial one - instead of the pissy little pistons in some of the more chav dump valves - these are twice the size and get rid of every last bit of air...

 

Ian

I will be running a stage 3 TT t35 at 2 bar of boost and no dump valve is required.

I have a mate who has a GT30 on his saff, and Karl has advised him to run one due to weak internals of the GT series.

Get a T34, wind it up to 28psi, and STILL leave it off!



Get it on ebay, and get a free half tank of fuel!

 

ive ran a t34 .63 at 30psi for nearly 2yrs with no dv and never had a problem

 

I don't notice mine.

Why are you all against them ?

I thought it helps throttle response and saves your turbo ??????

Steve.

 

Ive got one too, it dosent bother me

 

Love mine , chatter and whoosh , ohh yes please , never ran one before as was against them , but its a great noise from under my bonnet with both on the go

 

rabmc

try taking it off and see what the stall is like then

 

just run a re-circ, all of the positives with none of the negatives

 

i use one on my T38....i'm on a standard airbox again now so i need some noise!!!!

it's not a chavvy one though and doesn't dump when just cruising....i used to get pissed off with bailey ones as they keep dumping when your on the motorway at steady cruise!!

 

I have got one on my Rs Turbo but will be taking it off when i get the car set up again as it's getting on my tits now



Brian

 

When transitioning from a boosted state to a closed throttle state (as in between gear changes), due to inertia a turbo continues to pressurise air, but the closed throttle prevents the compressed air from entering the engine. In this case the pressure exceeds the preset spring pressure in the dump valve and the excess pressure is bled off to atmosphere.
Even with a dump valve the compressed air acts as a brake on the turbo (slowing it down), because the pressure on the backside of the turbo is at a higher pressure than on the front side (and the air actually wants to flow through the turbo backwards, in high boost situations this can create compressor stall or apparently damage turbine bearings or blades - 'but I have never seen it').
A blowoff valve is a more elegant solution to this problem by allowing the turbo to "freewheel" when the throttle is closed (equalizing the pressure on both sides of the turbo). Blowoff valves are sometimes incorrectly called dump valves because they serve a similar function, however they are very different solutions to the same problem.

 

bin it

 

mmm ok

seeing as most of the consensus is to get rid, ill take it off the weekend.

 

"When WOULD you fit a dumpvalve?"

When I wanted to impress the 14 year olds down the local cruizzzzzze [/b]

 

surely you prefer the chattering of the turbo without the dv as opposed to psssssss, o and the performance positives

 

indeed i do

Just wanted to know if safe to take it off tbh, as you hear so many different things etc,

 

except if it leaks and fucks it all up!

 

Told ya so, Told ya so

nerrr nerrrr

 

I bought GGR racing diaphram one and it don't make no noise all I can hear is turbo chtter


Luciano