VNT: has anybody...

[bluespanner]

... Invented a method of controlling one properly yet? There are a great many in the scrap yards but most people, myself included, don't know how to make it work. From what I read, the boost controlled ones aren't ideal, I have also seen a rather agricultural looking setup on a VW forum involving linkages and springs.

I think there is a gap in the market for a stand alone box of tricks and a couple of sensors, (boost and throttle position maybe?) to control an N75 type vacuum controller to allow using a standard vac actuator. Being a bear of little brain, such things are beyond me, but not beyond the capabilities of some on here.

What say y'all?

[Jamie_grieve]

This lad's been at it and doing a grand job:

http://forums.lr4x4.com/index.php?showtopic=85308&hl=

[Aragorn]

This looks to do what you want as well:

http://dmn.kuulalaakeri.org/vnt-lda/

[Nigelw]

I forgot about Flashmantv

Will PM immediately!!!

[A Twig]

I believe Turbocharger of this parish has a lot of experience as well...

[Spongie]

two of my friends run Vnt (one of them a 2.5 v6 turbo and the other actually a VW 2.7 Van turbo) on 200tdi's both of which are well and truely tuned, but they both are using kinguawa boost actuators with much success, will try and get more details though as I'm doing the same as both of them!

[Anderzander]

A chap on AURLO said he converted his VNT to a boost actuator and that it ran fine. Yet the diesel tuning forums seem to discount that for a number of reasons.

[Ex Member]

The international 2.8 used simples direct boost control. It works fine.

[Turbocharger]

Mine is boost controlled. It doesn't get the last ounce of benefit, and does spike a little in fast transients, but it's 85% of the solution for 10% of the complexity.

I've a diaphragm which effectively reduces the boost as pressure builds. The size of the diaphragm, the spring force and the preload are the variables I tuned to get the final answer, and I've still got a bag of spare springs but I'm pretty happy with the result now.

[Anderzander]

Turbo, did you do a 'build' thread for your turbo install ?

I'd love a vnt on my td5 but the cost of a bolt on conversion and the complexity of an electronic control for the boost are both huge barriers.

[Turbocharger]

Yep, there's a build thread on here somewhere, search for "Turbocharger 300Tdi VGT".

Once a mate had welded up a manifold for beer tokens, the rest was two-spanner rated tinkering.

[Lewis]

Here

http://forums.lr4x4.com/index.php?showtopic=29453&view=&hl=&fromsearch=1

But the images no longer work

[Turbocharger]

Not sure about the images but I've still got the real thing, available for viewing in exchange for Jaffa Cakes

[Nigelw]

I'll buy you a virtual pint if you post some piccies

[vulcan bomber]

A chap on AURLO said he converted his VNT to a boost actuator and that it ran fine. Yet the diesel tuning forums seem to discount that for a number of reasons.

The main one is that when your cruizing on the motor way, not needing much boost the turbo's veins cant open, causing back pressure and cosing a few MPG

[Anderzander]

Is that; more back pressure and MPG than an optimally controlled VNT; or than a standard Turbo (non VNT) in that situation ?

[vulcan bomber]

Is that; more back pressure and MPG than an optimally controlled VNT; or than a standard Turbo (non VNT) in that situation ?

More back pressure and LESS MPG than an a properly controlled VNT. Idealy a VNT wants to be electronically controlled but the normal systems used are kak, vac controlled is better, mechanical control is kak, microprocessor is the best if you can make one work. 1 day in the distant future i'll do it this way with an electronics geeky friend of mine and i'll do the FIP as well.

[Anderzander]

Sorry I wasn't clear - what I meant to say was is how does that scenario compare with a non vnt turbo.

[RustyNissanPrairie]

so what about the options from BAS and Allisport and their off the shelf VGT options? are they any good or should I be tinkering myself?

http://bellautoservices.co.uk/store/defender-200tdi-vgt-hybrid-turbo/?submenuid=56

http://www.ebay.co.uk/itm/AlliSport-Land-Rover-Defender-200-Tdi-VNT-Turbo-Direct-Replacement-Turbocharger-/251189661048?_trksid=p2047675.l2557&ssPageName=STRK%3AMEWAX%3AIT&nma=true&si=dpYFgQmWidjMxnBBHd%252FnzAonm30%253D&orig_cvip=true&rt=nc

[Anderzander]

From what I've read they are excellent - but too pricy for me.

[vulcan bomber]

so what about the options from BAS and Allisport and their off the shelf VGT options? are they any good or should I be tinkering myself?

http://bellautoservices.co.uk/store/defender-200tdi-vgt-hybrid-turbo/?submenuid=56

http://www.ebay.co.uk/itm/AlliSport-Land-Rover-Defender-200-Tdi-VNT-Turbo-Direct-Replacement-Turbocharger-/251189661048?_trksid=p2047675.l2557&ssPageName=STRK%3AMEWAX%3AIT&nma=true&si=dpYFgQmWidjMxnBBHd%252FnzAonm30%253D&orig_cvip=true&rt=nc

There both the same Turbo IIRC, the same turbo as the 2.8TGV engine.

[vulcan bomber]

Sorry I wasn't clear - what I meant to say was is how does that scenario compare with a non vnt turbo.

Different ball game, its like comparing a Land Rover to the Space Shuttle.

[Anderzander]

Lol - I think I still haven't managed to articulate my question. I must be tireder than I realised... But thank you for your efforts !

[A Twig]

I had some chats with Mr Turbocharger a while ago, we ended up concluding that some sort of basic electronic control wouldn't be that difficult ( I think ), the main issue would be the time to do all the calibration...

[Anderzander]

Let me have one more go ....

Would a boost controlled VNT, incurring the MPG reduction as described, still compare favourably (consumption wise) to a standard turbo on the same engine ?