Author Topic: can a diesel turbo be used to convert a g40 to turbo?  (Read 5940 times)

Offline Gaz_golf_gti

  • Members
  • *****
  • Posts: 49
can a diesel turbo be used to convert a g40 to turbo?
« on: June 10, 2009, 02:45:23 pm »
hi all its as tittle says rearly can a turbo from say a passat turbo diesel be used to convert a g40 to a turbo i have been told some turbo's can spin the opposite way is this true?

cheers gaz

Offline hayesey

  • Administrators
  • *****
  • Posts: 5824
  • The CV joint killer
    • ClubG40
Re: can a diesel turbo be used to convert a g40 to turbo?
« Reply #1 on: June 10, 2009, 03:14:13 pm »
generally speaking you can't use diesel turbos on petrol engines.  A petrol engine turbo needs to be able to run quite a lot hotter than one on a diesel engine.  As a result manufacturers usually use cheaper materials and production methods to make diesel turbos than petrol ones because they can get away with it to save costs.  I have heard stories of people melting turbine housings using a diesel turbo on a petrol engine.

Not worth bothering about when K03 turbos from petrol engined passats and audi a4s are so cheap and easy to find.

Offline Vizor

  • Members
  • *****
  • Posts: 27
Re: can a diesel turbo be used to convert a g40 to turbo?
« Reply #2 on: June 10, 2009, 03:49:54 pm »
easy to find in England :) not in Bulgaria

hi Gaz_golf_gti .. i'm with that turbo (i mean from diesel 1.6 passat engine) k14 and turbo is still fine perfect :)
with good oil and exploatating.. everything is fine
but.. i have boost at 4k rpm 2nd gear

Offline Tommo

  • Members
  • *****
  • Posts: 292
Re: can a diesel turbo be used to convert a g40 to turbo?
« Reply #3 on: June 15, 2009, 05:19:50 pm »
There shouldnt be a problem using 99% of diesel turbos, just make sure you do the maths to make sure it will work ok. Generally speaking the same turbo will make 2/3rds of the power on a diesel engine as it will on a petrol. So if you get a turbo off a 120bhp diesel then it will be perfectly happy running 180 bhp on a petrol engine. This is only a rough guide though. Also diesel turbos tend to have quite small turbine housings, making them ideal for small engines such as the G40.

Many garrets share component part numbers between petrol and diesel orientated turbos, so I wouldnt worry too much about the quality of the materials, to be fair you probably arent going to be doing mega milage on it anyway im guessing.

Another advantage to running diesel turbos is that they are designed to run a lot of boost, as most TD engines run upwards of a bar. Some older petrol garrets dont like running a lot of boost because of weak thrust bearings, at least with a diesel turbo you know it can handle a bar going to the moon and back.

Personally I would be looking at turbos off 2.0 litre TD engines and upwards. If you find a turbo send me the serial number and I will let you know the specs.

Offline Gaz_golf_gti

  • Members
  • *****
  • Posts: 49
Re: can a diesel turbo be used to convert a g40 to turbo?
« Reply #4 on: September 05, 2009, 08:27:12 pm »
nice one tommo im not very good at maths as im dislixic (dont no how to spell it) could get my grandad to work it out as he is amazing with maths lol

what sort of calculations will i need to work it all out?

which diesel turbo would you advise?
am guna try and push the standard block to or over 200bhp lol maybe need a space ship to bring mi cylinder head back from the moon though lol

cheers all for your input muchly appriciated
gaz

Offline hardchargin40

  • Members
  • *****
  • Posts: 438
  • Older, Wiser, Greyer.
    • The Roadster.net
Re: can a diesel turbo be used to convert a g40 to turbo?
« Reply #5 on: September 17, 2009, 01:23:01 pm »
Can the latest variable vein TDi turbo be used?  Would it still work similar in a petrol car as a diesel as in pull from nigh on nowt rpm?


A few peeps on pug forums selling new/unused GT25R's btw somewhat cheaper than RRP (usually £900 mark) at about £450.

Offline lance

  • Members
  • *****
  • Posts: 921
Re: can a diesel turbo be used to convert a g40 to turbo?
« Reply #6 on: September 17, 2009, 04:05:02 pm »
you got a link to them people selling turbos?

Offline hardchargin40

  • Members
  • *****
  • Posts: 438
  • Older, Wiser, Greyer.
    • The Roadster.net
Re: can a diesel turbo be used to convert a g40 to turbo?
« Reply #7 on: September 18, 2009, 09:42:43 am »
I'll try and dig out a link for you, saw it a few weeks ago though...