leecavturbo

iirc garrett say it is required for GT Series Turbo's running high boost.
other turbo's possibly run forever without one like you say

leecavturbo

i know what i'm sticking with. hate the sound but
you just know relieving unwanted pressure has
to be a good thing ?

scoooby slayer

iTrader: (4)

i totally agree i wouldnt run 2 bar + without one

Stavros

ALL turbo companies will say you need one, it covers their arses a bit more as in theory it WILL take some of the strain off, though the reality is there isnt much strain anyhow.

One thing we dont know, will need Christian to tell us, if did this happen as he let off the throttle?
If not its got fuck all to do with DV or not as it

Kev.H

yeah but on a diddy focus you aint ever running 2 bar without going pop 21psi wonder what that track focus runs he had standard manifold etc maybe just remap, decat etc

dumped

Surely its only to get rid of shock loads from the compresser stalling. I thought they first came about to stop the pigeon mating noise lol then folk started to vent them to atmosphere as a "look at me"

s2 ben

am i missingsomething when did christian lose the top speed record and by who

Martin-Hadland

iTrader: (2)

IMO GT series turbo's DO require a dump valve, Porkies car has 2. We did exactly the same damage as C&B on the dyno when we ran my old Millington engine without a DV.

Kev.H

I prefer a pigeon turkey chuckle rather than chuffing my recric still makes a stupid chuffing noise when I have the kone air filter fitted

Rod-Tarry

Check his sig thats all i can say the mag will reveal all, i rather slipped up

Kev.H

Is it better to run a DV or a Re Circ Valve

dumped

If this seems to be the case I would say that GT series turbos sound weaker. I have seen a lot of "undumped" boost run though conventional T series turbos with no dump valves with no issues over a good lot of testing. A good range of sizes too including some larger ones.

Have these turbos "honestly" not been subjected to surge as well as not being "dumped" As this would make a more sense for them to be getting a lot of abuse? Would guess its a factor.

leecavturbo

its the relieving of the pressure that counts so either
i'd guess.

RWD_cossie_wil

iTrader: (9)

I have to agree with Martin here, what happens to all the air when a throttle is snapped shut from 7500 RPM? That is a LOT of air, the turbo which is possibly doing close to 100,000 RPM will get a big shock loading with the air suddenly "stopping" infront of it, which will cause the compressor to choke and again the pigeon noises you hear is actually surge, air being forced backwards through the blades which can quite happily destroy a turbo.

It is a very under estimated effect, I work on aircraft, and have seen the damage to engines when they surge, it is scary how much damaged compressed air can do ... The jet engine is basically a turbo with a combustion chamber in the middle, I will post some pics up of a surged engine when I am back at work, you can see all the compressor blades bent the wrong way ....

So I would ALWAYS run a dump valve on anthing bigger than a T34, remember a T4 has the same size shaft as a T3, and the GT series have bigger wheels front and back, so the leverage against the shaft will be much greater than a T3 etc..... If you don't like the DV noise, use a recirc valve.......

Hope you sort it christian, don't let the fuckers fob you off ,I had a BRAND NEW T34, that threw its guts after 300 miles , just after the car had had an oil and filter change, and got the old "oil contamination" excuse , but after a bit of an argument they honured the warranty

Christian and Beccy

iTrader: (14)

To clear this one up, I don't currently run a Dump Valve, but I don't run 2-bar of boost either, the failure occurred at 1.8 bar. That said, I am going to run one if it goes back together.

However, the turbo failed at 160mph, which is well into 5th. I'd have shifted into 5th at just after 130mph, so don't think the DV would have helped this.

My decision to run one is more because I am happy with how Gary's is with his DV (noise etc) and for the sake of the cost of it, I will err on the safe side.

If it makes the car run like shit, it will come off again.

Rob M666SCC

Have you considered the EGT's ???

Stu.H

Daz runs 2 DV's on his dolomite as well

Mike Rainbird

iTrader: (3)

That is exactly what happened to AndyG's GT turbo (doing the same kind of thing), except his happened with throttle lift off . This is why I personally don't like the small GT turbos as in the aid of quick spool up, the shafts are made relatively spindly compared to the T series ones.

If I had one of these turbos, it would DEFINITELY be fitted with a dump valve, as although Christian's didn't fail in a lift-off scenario, it could have been an accumalitive amount of damage from previous lift-offs that twisted the shaft until it finally had a catastrophic failure.

Porkie

iTrader: (1)

Gutted for you mate

Fooking cars

My Skyline lunched its Turbos at Brands Hatch I wasn't even driving it!

Modded cars man... proper pains in the ass!

Kev.H

please someone is a recirv valve as good as a dump valve

Mike Rainbird

iTrader: (3)

Its the same you gimp, it just doesn't vent to atmosphere .

Charlie Chalk

iTrader: (1)

Yes.

dojj

iTrader: (3)

i've been in this position plenty of times before

what you will do in a few months after you've got rid of the car will be to justify the whole cost issue of stopping all this "fast car nonsence" but in the back of your mind there will always be that lingering doubt that you could have sorted the problem fairly easily

always the easiest thing is to give up, and sure, you can give up, but park the car up somewhare out of sight and in a few months come back and say "right youlittle git, let's find out what went wrong" and then you'll feel much better

and the sun'll be out too

M K

iTrader: (9)

my gt30 doesnt run a dv......and i run anti lag with it too was told it will be fine as the als will not see more than 900deg i think tommy said,

i have surge issues tho

Twellsie

iTrader: (1)

[quote="Kev.H"]please someone is a recirv valve as good as a dump valve [/quote

effectively the same thing, dump valve vents to atmosphere, recirc vents the air back into the induction system but both do the same job

Kev.H

good job for you then cos I would of wanted a refund on my re circ for a dv which I beleive you sold me