upgrading turbo on diesel A4

Ish

Ish

Ish

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West Midlands
Hi

A mate of mine has an Audi A4 with the 1,9 PD engine. His turbo died so he decided to make a 2wd cossie T3 turbo fit the car.

He has managed to make the turbo fit the car with some fabricated parts and is just waiting to sort out the oil pipes.

My questions is what problems do you think he will have with this conversion and will it work?

How will he add extra fuelling in for the extra boost (providing the turbo works out ok). Can the ecu be remapped?

Anything else he should have thought of or be worrying about? lag?

He will be upgrading the intercooling but the rest of the engine is totally standard.

Thanks
 
More fuelling comes from bigger injectors with a diesel, that's pretty much it. Probably get a bit more lag if it's a bigger turbo :D
 
www.tdciforum.co.uk

Probably best to ask there, my first thoughts are that the turbo is going to be far too big for the diesel engine, and therefore won't spool up when it needs to..

EDIT - Read your post properly this time :o People can do custom remaps, theres a chap in poland ( contact details are on above url IIRC ) who will customise your ecu file after a few discussion emails with you, then send it back for you to stick on the car.

Your also going to need bigger injectors..
 
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[TW]Fox;11784286 said:
Given who you are surely the Reyland lot know more about tuning turbocharged cars than OcUK :confused:
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He's on holiday so I can't as him!

My initial thoughts on this was that it would be a horrible car to drive as by the time the T3 is producing decent boost there won't be much revs left but I've never looked at diesel tuning so could be wrong.
 
There is a very good reason that turbo diesels have tiny turbo's, to help them produce useable boost at low RPM so you can make best use of the limited RPM range of these engines. A diesel is typically producing useable boost by 1500 RPM, a 2 litre petrol will typicaly be at least 1000RPM up from that. If this is the case on your friends car he will have made it significantly slower, even if he can increase peak power by adding more fuel.
 
Dogbreath said:
There is a very good reason that turbo diesels have tiny turbo's, to help them produce useable boost at low RPM so you can make best use of the limited RPM range of these engines. A diesel is typically producing useable boost by 1500 RPM, a 2 litre petrol will typicaly be at least 1000RPM up from that. If this is the case on your friends car he will have made it significantly slower, even if he can increase peak power by adding more fuel.
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Diesels have tiny turbos? :P


Granted the only ones Ive really seen were either on marine engines or in my 2.5 A4 but they werent exactly tiny :P
 
Phal said:
Diesels have tiny turbos? :P


Granted the only ones Ive really seen were either on marine engines or in my 2.5 A4 but they werent exactly tiny :P
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Of course they are tiny, you dont have a hope in hell making full boost at 1500rpm on a reasonable sized turbo
 
Bear said:
Unfortunately on a fsmall our pot its virtually pointless
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You mean like BMW have done with the 2l diesel and produced the most powerful factory supplied 4 pot diesel ?

Diesel turbos also produce a lot of boost even as standard they produce around 1 bar, the bigger turbos are pushing 1.5-2bar boost on the 230-270bhp 1.9 PDs. I am not sure what boost a T3 turbo can produce reliably but its going to need to be putting out at least 1.5bar to make it worth while. A standard remapped 130PD turbo is hitting 1.2ish bar depending on map and that would produce around 185bhp/300lbft.

The people he should talk to a Allards they are the best when it comes to diesel tunning.
 
Well the turbo youve linked certainly is small... but the replacement turbo I got for my A4 was about the size of a football with pipes sticking out, certainly not really what Id call small.

Guess the more modern engines have smaller more efficient turbos :\ suppose it helps with the economy
 
Rather than outright size, most modern diesel turbos make use of VNT to optimise them for flow.

A T3 isn't going to be much to write home about on a 1.9TDi...At full-bore, it is going to be doing half the revs of an equivelant sized petrol engine which means that the turbo is only going to be seeing half the gas (in terms of CFM).

Then you have the fact that diesels are more efficient than petrols and the exhaust gases are much cooler so the energy transferred to the turbo in order to make it spin is much, much less...

*n
 
jaykay said:
Saab have also used this idea on their car as well.
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Its a 1.9 aswell. Meh so you use sequential turbos so you have virtually no lag over the measely rev range, the tiny turbo will have to probably work its nuts off and drop dead by 40k miles. I still think its virtually pointless.
 
Vauxhall did a twin turbo 1.9 diesel too, it obviously works otherwise numerous manufacturers wouldn't be doing it.

edit - Vauxhall and Saab both the same GM engine?
 
I imagine that turbo will be awful on that lump. A T25 on a 1.9 derv produces a chunk of lag (cough, boost threshold) a T3 is going to be much worse; keep us posted!

http://www.racingtdi.com/main.htm <-- 1.9 VAG DERV lump @ 240BHP. Can't remember if it is PD or not, suspect not but same principles should apply considering people have managed to whack VGT turbos on 306s...
 
Since he had got so far with it he decided to try it with the T3 and as predicted it was lag city! :eek:
 
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