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Old September 10th, 2010, 05:28   #1
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Default My AHU Corrado VNT GT1749va Turbo Build Thread

I am planning to an a B5.5 VNT GT1749va turbo to my AHU. I already have the turbo, AFN manifold and now I want to get the misc parts so I can fit the turbo in the spring (yes a long build thread).

One of the best threads I have found for this upgrade is right here:

First let me say that the 1749va is a small turbo upgrade. I'm looking for anywhere from 140-165whp without an IP upgrade and 170-180whp if I upgrade to an 11mm IP. I don't plan on upgrading the IP unless it begins to fail. An upgrade for this 1749va turbo is the BV43 turbo which is talked about here:

Some of the reasons why I'm using this turbo is the price that I was able to get the manifold and turbo. Also this setup should clear the rear motormount & bracket.

I want to use as many factory parts as possible. I was able to get the Turbo NEW from VW for an excellent price, so good that I will have one spare on the shelf for the future (incase this one fails) and I'm rather frugal.

Here are some pictures of the 1749va compared to the GT15 (same as the kkk kO3):

The 1749va sits closer to the #2 cylinder then the KKK k03 which is almost centered between #2 & #3 cylinders so the AHU oil lines will be the wrong length but otherwise would connect to the 1749va.

My research on shows that the oil line part numbers are:

MK3 AFN Oil Return Line: 028 145 736 AB
MK3 AFN Oil Feed Line: 028 145 771 BE
Mk3 AFN Air Inlet Pipe (I think the AHU part will work) 1H0 129 965 N (1H0 129 965 P for Cold Weather Climate[PCV Heater])
Mk3 AFN Oil Line Bracket/retainer 028-145-859-J for AFN engine 1996 TDI Passat/Golf
Mk4 038-131-501-AN EGR Valve Replacement for 038-131-501-S on the AXR Engine- 2002 Golf TDI

Parts I have:
I have the 1749va
AFN Manifold
130 PD intake manifold and adapter *Installed*
PP764 *Installed*
mk4 N75 Valve
2" IC pipes *Installed*
Kerma Turbo Compressor Outlet adapter
AFN oil lines
AFN Turbo Inlet

Things I still need to get:
*downpipe, I was planning to build my own until I found a really good price on a NEW OEM downpipe and cat on the UKebay I'm just waiting for it to arrive any day now.
*ECU Modified
*adapter to the 2.25" cat back exhaust
*I might even try to get an EGR valve that works on my PD130 intake manifold so that can be fully functional. Time will tell. I know it might reduce power but I like the idea.
*Mandrel bend to adapt the IC pipe to the turbo outlet.

Finished list for others that want to put a b5.5 turbo on their Mk3/b4 1Z/AHU:
  1. AFN Oil Return Line: 028 145 736 AB
  2. AFN Oil Feed Line: 028 145 771 BE
  3. AFN Air Inlet Pipe (I think the AHU part will work) 1H0 129 965 N (1H0 129 965 P for Cold Weather Climate[PCV Heater])
  4. AFN Oil Line Bracket/retainer 028-145-859-J for AFN engine 1996 TDI Passat/Golf
  5. Exhaust/Turbo Manifold
  6. downpipe
  7. ECU Modified
  8. IC pipe to the turbo outlet modified
  9. N75 Valve
  10. Vacuum accumulator
  11. Reroute the vacuum lines

here are some pictures of my Engine bay and my AHU Corrado:

Oh and my upgrade timeline has been moved up because I made a mistake while doing my timing belt job and didn't remove my ratchet from the crank after making certain there was no interference after tightening up all the bolts during the timing belt job. So now I am going through the engine. The block will be getting new rings, the head is being rebuilt, the injectors balanced and the cam is being upgraded to a colt stage 2. I had wanted to rering the bolt at some point, I'm just frustrated that I'm forced to do it because of my mistake. At least its during the winter.

Link to a spreadsheet with part numbers, prices and sources A_Turbo_Costs_and_Parts.xls

Below are links that I'm storing here so I can begin compiling a decent AHU/1Z upgrade thread (I'm tired of searching for everything.)

AHU vs ALH discussion and includes a slight discussion of pistons:

Be careful when swapping injector pumps(see post 36):

Some of the AFN or VNT threads that I have found helpful for this swap:

AFN Vacuum line routing:

AFN Wiring Diagram:
AFN Wiring Diagram

Good thread explaining the flow for the various injectors:

AHU & 1Z Intake Manifold Threads:
PD manifold with an EGR for a Mk3/B4:

Adjusting the EGR Opening Cycle (won't turn it off but it can decrease it):

Checking & Adjusting the VNT Actuator:

AHU/1Z Timing Belt Procedure:

Adjusting Injection Quantity Technical Explanation of the Adjustment:

Injection Pump Timing (the mechanical process of the adjustment):
Which way to advance or retard:
Centering the pump in the mechanical adjustment range (do this before putting the belt on):
When adjusting make certain you loosen all of the bolts:

Injection Pump Timing Discussion of where the setting is best:

Finished Specs of my car:(September 2011)

Engine: 1.9L AHU from a 1998 Jetta with a Passat wiring harness
Transmission: Mk3 O2A "CTN" transmission

Brakes/Drivetrain: 5x100 Lug Conversion (Eurospec Sport Conversion Hubs), 11.3" Mk4 GTI rotors, 5x100 rear Rotors, SS lines, Mintex red pads

Suspension: H&R coilovers, Neuspeed 4 point rear strut bar (modified for Quick removal) R32 control arm bushings, New Strut Bearing Bushings, New rear shock bushings.

Wheels & Tires: 16" Audi TT wheels (Very Rare) that have been stripped of their paint and Polished. Yokohama Parada spec 2 Tires 205/40/16 Tires

Exterior: Stock Body work with 20+ years of minor wear and tear with the original paint. Tinted/Red taillights, clear side markers and European headlights. 90mm Front Euro Lip Lip. Passat Moonroof Conversion. The Moonroof interior panel has a grey cloth panel that matches the OEM headliner perfectly.

Interior: Stock Black Heated Leather with a TDI Passat instrument cluster with MFA 100% operational. Auber EGT, VDO boost & oil pressure gauges. European manual seatbelts. 337 Pedals

Audio/Visual: Late Mk3 Jetta Radio (matches the Rado's instrument lighting) No more amplified door speakers

Drivetrain: Approx 175k, the engine had 115K miles when I started the swap.
The shell had 59k miles when I started now at 120k

The car has an 15 gallon fuel tank and can get 48-52 mpg all day everyday with the 16s and driving it hard. 55-60 if I pamper it and try for economy. Why I think this car is so great? This is the car that I originally intended to build on my first TDI Corrado build, its all OEM like. Everything went together like it was built this way from the Factory.

The original build Thread:

Photo Album:

Last edited by G60ING; March 1st, 2013 at 11:31.
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