Been running No DV with a VF23 for 6 months now, 3 hard track days and all is fine, With the front mount there is a very load chirp much like the big powered cossies and gear changes are very direct,

Only down side seems to be on track where the wastegate doesnt know what to do on part throttle, other than that its much better than a dump valve,

 

Is it hard fact that the early VF's cant cope or is it just urban myth ?
Its not a dig at anyone, just trying to find out.

 

hi ive got a 03 wrx still runnin standard turbo with i fink iz a td04 can these cope avin no dv?cheers

 

Personally I would not run an early VF without a dv but its up to you if you want to risk it. A TD04 should be ok with no dv as the TDs are a lot stronger than the VFs

Banny

 

Thats answered my question

 

Can't beat a bit of plastic diy plumbing for weight saving..!

Hadn't thought about those washing machine 'bung's, are those the ones that taper and about 3" in length..?

Once I'm certain I'm happy with no DV I've got some thin ally bar that I can Knock a plate out of. The intake end I hadn't thought about yet, but it looks like a trip to B&Q is in order..

Can anyone tell me what the internal diameter of the intake to DV hose is..?

 

I've been converted to running no DV. I was actually advised to by several highly regarded experts when going to the FMIC, but people considering it should be aware of one downside on maf based ECUs: it can make the car judder a bit when doing on and off throttle transitions. AFAIK this is because the maf registers air coming back the "wrong way over the sensor" and just erroneously adds fuel.

My squirrel blender sound is rather on the loud side as I have a FMIC and K&N cone filter; certainly gets the attention of people in the car

For what it's worth, the advice I've always been given (again, by tuners and mappers) is VF30 onwards fine with no DV, earlier than that and you're risking it! Take it or leave it

 

I've actually found my car is a LOT smoother with no DV compared to the BOV I was running. I am still running the MAF as well.

 

What could I use with a phase two classic uk engine? Would I have to have a plate made up as the intercooler is different from the earlier classics?

 

BUNG!!!

 

VTA per chance? If so or with some aftermarket recirculating ones, that'll be why

I went from the std recirculating one.

Ns04

 

So I take it the oe hose is 32mm..?

That will do very nicely.. Just need a short piece of 32mm hose, as I don't want to cut original, just in case I decide change back at some time.

FWIW, after more evaluation today , the response after up-changes is much sharper. With slick changes the power is almost seamless with no appreciable dip, even when short shifting.

Looks like I'll be staying DV free..

Finally, I've not noticed any juddering (yet) and car does seem smoother, this was after removing OE DV BTW..

 

Litmus test: Motorway: 5th gear, get the car's boost building and at about 3.5k back off and see if you get some judder!

 

Did you get anymore over boosting?

 

Yep, was a VTA

 

A little, but not what I'd call over boosting, just peaking a little higher longer.. I'm going to try and get out today for a proper run down my local test route.. I'll also try NS04's litmus test in 5th to see if there's any ruddering.

Will post back later..

 

You wont need a car for that.

 

Highly regarded technical word is ruddering..

Sorry, I was replying to a post on xxx.net at the same time..

 

Here's a quick pic of the blanking plate I got made.

 

chrisdicko, in addition to the two OEM bolts, did you also bond the plate to the flange by using some liquid metal glue too - for a perfect airtight seal?

 

I dont get it. Are you all saying no DV is better? That the DV does not stop the turbo stalling? Or is this just the placebo affect?

 

I may be wrong, but I assume that the benefit comes from not having to repressurise the intercooler pipework and core (this will be most apparent on cars with a FMIC). Yes the turbo would stall, but should get back up to speed very soon once you are back on the throttle.

 

That's what I was told If memory serves.

Ns04

 

i ran an uprated recirc valve on mine, it was modified to give a higher clamping pressure and i would guess that at 90% of its life, it was shut, full boost/throttle changes would open it, the rest of the time it was clamped shut, and i suffered no ill effects.

 

Yeah, the above is probably a better solution...

When there's lots of really compressed, hot charged air between the DV and TB, then it'll be a bit kinder to the turbo thrust bearing/shaft, as the DV will actually open fully after those specific full boost/high load/WOT conditions.

 

Is it possible to put a stronger spring in the standard one? I have access to lots of springs at work?

 

Zebedee?

 

Tried the 5th gear test and no judder (or ruddering for that matter, lol..).

The car is much stronger through the gears, with instant power, not that I ever thought it wasn't previously, so quite impressed..!

The only thing that concerns me slightly is the peak boost of 1.7bar, up 0.1 on it's mapped target..! I've emailed Bob and awaiting his reply. As far as I'm concerned if the map needs tweaking then I'm prepared to have it done to ensure things remain safe. I've also noticed some surge (boost gauge fluttering a little) when going WOT mid-range in 4th and 5th. KL, so far has only shown greens once on a full bore up change.

NS04, I seem to remember you had surge issues, did this ever get fully resolved..?

 

Glad you're not getting judder......I wonder why? You're not using an aftermarket ECU or running a blow through maf are you?

Surge still there a bit on WOT sometimes in 5th, but that's due to the VF35 which is a "lively" turbo!

 

Joz, there is a small black gasket under there, which I think may keep it air tight.
Might try squiring some fairy liquid leak detecor on there to check though!!