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Author Topic: 2.8 MTDI with VNT turbo brazil international engine  (Read 3856 times)

April 25, 2014, 07:37:43 pm

snakemaster

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2.8 MTDI with VNT turbo brazil international engine
« on: April 25, 2014, 07:37:43 pm »
Dig up this info may be intresting to some and may not of been posted before , this engine is based on the good old land rover 300 tdi but rins a VNT turbo thats controled from the fuel injection pump , dont no to much about it ,and not had to much time to study up , but be good to find out what other pop think , Turbocharger design is often a compromise, with large units providing the large volumes of air that engines need at speed, though it won’t spin up to speed so quickly during low-speed acceleration, producing turbo lag. A small turbo will accelerate quickly but may be short on output at high speeds. Using the variable geometry allows a constant boost pressure available from idle so there is no delay or lag when accelerating. Coupled with the Bosch VP14 mechanical fuel system (no electronics), the end result is improved acceleration and maximum torque achieved at a low 1400rpm compared with 300 Tdi’s 1800rpm or the Td5’s 1950rpm.
http://www.ebay.co.uk/itm/251195067044?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
i asked the guy this good power inprovments looking to upgrade my turbo i have had a read up but not shure how the turbo is controled as it is a vac type , and all the diesel cars have a ECU to control the VNT turbo  , is this the same dose it come in the kit

reply This is a totally mechanical VNT, it is operated by boost pressure signal from the injection pump.
there is a pic of the turbo actuator, and a link with more info
https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCwQFjAA&url=http%3A%2F%2Fwww.aulro.com%2Fafvb%2Ftechnical-chatter%2F181988-boost-pressure-international-2-8l-engine-vnt.html&ei=7u5aU_ebFaOI0AXz_4EI&usg=AFQjCNG3oiNWH6mAstbpr4DK5SWKgeiYPg


Glenmorangie  single highland malt

Reply #1May 14, 2014, 01:04:21 pm

snakemaster

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Re: 2.8 MTDI with VNT turbo brazil international engine
« Reply #1 on: May 14, 2014, 01:04:21 pm »
would this turbo actuator work on our MTDI and not boost spike , and run at 3psi at 50mph on a flat road on no load .i just dont no if this could work how a vac E one would . any one tryed this turbo actuator,
Glenmorangie  single highland malt

Reply #2May 14, 2014, 04:48:45 pm

vanbcguy

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Re: 2.8 MTDI with VNT turbo brazil international engine
« Reply #2 on: May 14, 2014, 04:48:45 pm »
I don't see how it would work?  How does it know that you want less boost at low throttle input?  It seems like it would just be trying to close the vanes all the way with that set up, and then open them when it sees boost.  This will generate very high exhaust manifold pressures and deliver poor fuel economy.  It would also be bad if something goes wrong in the system - ideally you want the turbo to default to 'vanes open' if there is no input of any sort, as you can easily overspeed and blow your turbo if they are closed all the way.

While I've been testing my VNT it's really quite apparent just how restrictive closed vanes can be.  Coasting along in gear with your foot off the pedal and cycling the vanes causes a noticeable impact.  As in close the vanes, the car slows down more (more drag), open them and it moves more freely since now the engine can pump air out of itself again more freely.

Bryn

1994 Jetta - AHU M-TDI - Jezebel Jetta
2004 Jetta Wagon - 1.8T - Blitzen

Reply #3May 15, 2014, 07:45:28 pm

CdnVWJunkie

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Re: 2.8 MTDI with VNT turbo brazil international engine
« Reply #3 on: May 15, 2014, 07:45:28 pm »
Interesting!  I'd have to wager that if the factory is using the set up, you'd assume they had done ample testing. 

They won't be in our part of the world anytime soon so any other members who might run across one, we'd love to hear reviews.

Reply #4May 15, 2014, 07:47:27 pm

vanbcguy

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Re: 2.8 MTDI with VNT turbo brazil international engine
« Reply #4 on: May 15, 2014, 07:47:27 pm »
Interesting!  I'd have to wager that if the factory is using the set up, you'd assume they had done ample testing. 

They won't be in our part of the world anytime soon so any other members who might run across one, we'd love to hear reviews.

The way I read the eBay link, the seller is saying that the VNT is an 'upgrade' for the stock fixed turbo.  I'm not so sure it was ever used factory...
Bryn

1994 Jetta - AHU M-TDI - Jezebel Jetta
2004 Jetta Wagon - 1.8T - Blitzen

 

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