Anyone in the UK converted an AHU / 1Z to run VNT? - TDI Engine -General Info - VWDiesel.net The IDI, TDI, and mTDI source.

• Anyone in the UK converted an AHU / 1Z to run VNT? by MikkiJayne on 14 Aug, 2009 17:13
• Hey everyone 
  
  Well I've been quiet for a while, and I come back to find a shiny new forum engine!!
  
  Anyway, I'm about to ressurect the Corrado TDI and I have acquired a GT2052V for it, so I'm wondering if there is anyone in the UK running a VNT on an AHU or 1Z ecu? I know that you need to put the AFN software in it and run the mk4 N75, but I don't know of any tuners in the UK who can do this - only US based companies who are too hard to deal with.
  
  Does anyone have any suggestions?
  
  Thanks 
• #1 by ryanp on 16 Aug, 2009 13:02
• AFN passat n75 wiring and everything you need plugs in directly to the ahu, if you buy an uploader tool and a vag com i can put you in touch with a guy who maps cars over the net and has done this conversion to his car
• #2 by MikkiJayne on 16 Aug, 2009 18:37
• By uploader tool I presume you mean something like KWP3000? This is precisely my problem - the AHU is too old-skool to work with stuff like that unfortunately. It needs chips burning which as far as most UK 'tuners' are concerned is black-magic voodoo 
  
  Is your friend able to burn the chips? What car has he done this to?
  
  Thanks 
• #3 by gigaz2 on 27 Aug, 2009 09:22
• there are two ecus for these old tdis, the plastic case one (2 eight bit cpus, 28pin dil roms), and the newer 16 bit one in the aluminium case
  
  the newer ones accept the binaries for vnt and fixed geometry, the wiring can be adapted to run both, as the selenoids use different pins in the ecu
• #4 by MikkiJayne on 28 Aug, 2009 07:41
• Ah that is very useful to know thanks
  
  I have 1Z ecus with plastic cases with 28 pin dils and an AHU ecu with the metal case and 32 pin smccs so that makes sense.
  
  The AFN ecu seems to be the same as the AUH - same number with different software suffixes, so I shall probably source one of those instead, then that can just be remapped without having to muck about swapping software.
  
  Is it simple to disable the EGR in the AFN? My 1Zs are the early ones that don't care, so I'd like to make the new one work the same.
  
   
  
   
• #5 by G60ING on 28 Aug, 2009 10:03
• I will be asking for more information about your VNT swap as you get this going. How much do you think a AFN ECU will cost? How about an AFN Manifold, Turbo and downpipe?
• #6 by MikkiJayne on 28 Aug, 2009 17:04
• Hi Frank
  
  ECUs range from £50-100 here. There aren't many of the right sort about though as most of the AFNs were fitted to the B5 Passat here, and thats the later style case. The A4 and A6 seem to have them though, as does the Sharan. As for the turbo & manifold only the Sharan has a transverse fitment here so that is pretty rare, and the downpipe from that would be of little use in a Corrado I think (unless you cut it up).
  
  I'm going to fab a manifold & downpipe for the GT20, then I can put it where I want it I still have to find a suitable inlet manifold before I do that though...
• #7 by starrd on 28 Aug, 2009 19:52
• Jeff (Rocket chip) in the US can reprogram/Modify the GQ version of the B4 Passat ECU to make it an AFN equivalent in case you need another option.  The GQ is the updated 2 x 32 pin PLC C chip version ECU for the 1996 Passat.  When I contacted Jeff, he said I would have to send the ECU for modifications.  I'm wondering if it was to modify the output for the N75 valve (described above) so I didn't have to do any other wiring changes?
  
  Does anyone know the different pins for the AFN n75 output vs the stock waste gated turbo N75 output?  I have the AFN chip files, just don't know what ECU pin changes are involved.
• #8 by MikkiJayne on 29 Aug, 2009 05:11
• Thanks. I've tried RocketChip, but he is far to difficult to deal with from the UK 
  
  The reason he wants the ecu for modification is that the eproms are surface-mount soldered to the board, and so they need removing and sockets fitting. Thats just not economically viable from the UK as customs will charge based on the insured value when the ecu comes back, even though it was mine in the first place    Hence why I need to find someone in the UK (or EU). For me buying an AFN ecu is much easier, then I can get a remap for that which the UK tuners can do.
  
  Opinion seems split on the difference between N75 pins on the AHU and AFN. TDIClub seem to imply that they are the same    Unless of course it is so obvious to them that they never mention it... I have the diagrams, so I will have a look and post them up later.
  
   
• #9 by starrd on 29 Aug, 2009 10:37
• That is what has me confused.  The GQ ECU already has socket mounted PLC C chips, but he still said I would have to ship the ECU it to him for modification.  I ended up getting RC3 instead of going the AFN route and he just sent me the chips.  That’s why I am thinking it has to do with the N75 wiring.  There is another option for you - you could get a bolt in hybrid turbo and RC3 or equivalent.  Bora Parts sells the hybrid turbo https://www.boraparts.com/product_info.php?products_id=267
  It will run 18 psi boost all day.
  
• #10 by aidan on 29 Aug, 2009 11:29
• mikki contact rub87 on tdiclub, he sent me a chipped ecu from belgium. It was spot on first time, only for stock WG turbo but he was going to do a vnt map also, he'll give you the list of changes necessary
• #11 by vwmike on 29 Aug, 2009 14:50
• I've done the VNT software swap for a US Jetta 3. Since the US ECU's are socketed I just sent chips. It was based on some AFN software. You definitely need the correct N75 to make it all work.
• #12 by MikkiJayne on 29 Aug, 2009 15:51
• Interesting. I wonder why Jeff needs the ECU then 
  
  Thanks Aidan, but I already have the GT2052V. I nicked it off my A6 when I got a GT2056V for it
  
  If I can't easily find an AFN ecu then I will swap my AHU to sockets and go that way. I need to re-code the immobiliser either way as I don't have the transponder for the AHU, so it doesn't make a great deal of difference.
  
  
• #13 by G60ING on 29 Aug, 2009 18:32
• I just sold a JB ECU to a guy that asked that I send it to Jeff at rocketchip so he could modify it for a VNT setup. I'll be keeping in contact with this guy and once he has the ECU I'll update everybody on his progress.
  
  As far as the Sharan's downpipe, I'd be willing to bet it would fit since the Mk4 ALH downpipe actually fit nicely in the corrado
  
  I have a friend in Germany on an Air Force base and before he leaves I'll probably have him get the Sharan's pieces. Thanks for the info