Running without a DV- benefits other than noise..?
 

As title really..:)

I know a few have done it, NS04 in particular, as he runs a VF35 as do I, which iirc is up to running without a DV..?

I'd only consider doing it if there was a performance advantage from doing so, so that's the question, is there..?

Cheers guys..:thumb:

Yes there is, you will have quicker boost recovery after a gear change, smoother driving car when you come off the throttle and better throttle response in gear. All of which you need to beat bmw 335d's :D ;)

Banny

Is there any down sides to blanking off?

I have run my GT30 hybrid for 10k miles, without a dv and had it off recently and it is spot on.

Banny

No mate, I recon a rear mounted turbo's what's needed to beat a 335d..:p

;)

As chris says, downs sides apart from potentially recking the turbo are..?

Finally, to temp try it out, if I made a blanking plate to bolt between IC and DV would that be ok. As my boost gauge is tee'd off the DV I presume that wouldn't work, but just for an easy try out of no DV would that do..?

Now where's me tinsnips..?

Only other downside I noticed sometimes at higher speeds releasing the throttle causes a slight judder but nothing like a dv does.

Its crude but I dont see why it would not work as a try out, simpler way would be just get a silicone hose and a bung.

Banny

any standard turbos safe to run with no DV?

Anything from the VF30 should be fine without a DV I would think, as that started the new generation of stronger IHI turbos.

Banny

So to do it 'properly' you need to bung the inlet pipe, not a problem virtually the same as VTA crank mod only bigger bung and then seal IC where DV bolts to..:)
The only thing I'm not sure about (and I'm yet to look at it properly) is what about the small ~5mm vacuum?/boost hose that comes off the DV, which my boost gauge is tee'd into..? Is that also bunged, if so where do I plumb my gauge to..?:wonder:

Run the gauge directly to the feed on the inlet manifold remove the Tee piece, as the pipe going to the dv becomes redundant.

Banny

There is a time and a place for that type of talk ;)

Mine runs without a dump valve and I had a 20g turbo which I ran without a dump valve for a while :)

Of course, doh..! :D

I'm definitely going to give this a try, are there any implications with regards to fuel maps etc..?

I take it they do sound quite 'interesting' running without one..? ;)

Steve must has have seen a stunner walking past, while I was typing :lol1:

Spoke to Simon (JGM) regarding the fuelling side after the dv was removed and he goes wont be an issue.

If you have a silicone inlet pipe you are in for a treat in regards to the sound :thumb:

Banny

I am gonna try this too as I am running a VF35.

What are people using as bungs?

A suitable bit of silicone hose with jubiliee clips top and bottom and what ever holds best in the end :)

Already got the silicone hose running to DV as its a V4 so just need to find somat to put in it!

How was it with a 20g as that is my next turbo on my 2.5 conversion (with FMIC)?

Used one of these on a V2 STi.

Silicon hoses from Viper Performance

And for sale...

https://www.scoobynet.com/private-sa...ve-delete.html

For the little vac pipe, I'm going to use a stainless bolt from work.

It was fine, I never took any notice of noise etc. I only ran it for a few thousand miles then added a dump valve purely due to the fact I thought the car should have one ??? I think I notice the noise more now. Always reminds me of the "3 stooges" as its a sort of "woo woo woo" noise :D

What's the theory behind blanking off the DV?

As a BOV is used just for sound...and to make your car run rough :lol:

The Recirc makes the car run smooth.

Blanked off.....theory?

Yes, I had already emailed Bob and he said the same..:thumb:

Just running the oe inlet, but tbh I'm doing it for the performance first..:cool: Still I wouldn't mind hearing any vids/sound clips that might be knocking to see what I might expect, lol..:norty:

Those bungs look like nice bits of kit. Lol, I used plastic pluming bungs when I did the VTA, but they only come in 22mm max. The DV outlet pipe is ~32mm iirc..?

Thanks for the info Danny..:notworthy

A little clip of mine running no dv

MOV00123.flv video by hevalou - Photobucket

Sounds like the 'squirrel mincer', the P2 test on Top Gear

YouTube - Top Gear - Pro-Drive P2 Test Drive and Stig lap - BBC

Hmmm, just given it a go and it sounds like someone smothering a duck..:D Not loud, but that's down to the oe air inlet pipework/resonator etc...

Car does feel sharper on full bore gearchanges, but the thing that I'm a bit concerned about is my defi is now showing a peak of 1.7bar, 0.1bar above usual peak..! KL is silent. Could this be a 'false' reading, as all I've done to test out removing the DV is pop a plate between IC and DV, leaving all other pipework as it was- ie DV 5mm hose still attached to inlet manifold with gauge tee'd off..?

Mine over boosted too. Read 1.66 bar on my AVCR. Before it was only hitting 1.6 bar in the cold. I think I hit some sort of cut as well as when it hit this the car stopped for a second.

Maybe placebo but I also thort the car was better between gear changes too.

if you dont run the car with a dv i presume your using the standard dv as wont this cause alot of stress on the turbine shaft due to the exhaust wanting it to spin one way and the backpressure from the throttle body been closed wanting it to spin the other ???

Thats what causes the "chirp" noise, air being forced over the turbine blades.

Some turbos are strong enough to take it.

my car has a dump valve and its terrible when you pull of under 1500rpm and just go round town is this the reason or is it something else ?

could be the spring is not strong enough causing air to leak out the dump valve but i could be wrong

Do you mean you still have the bit of hose that previously went to the DV's vac nipple, still attached to the T-piece, now venting to air?!