Eurotrash Motorsports: W8 4Motion to BHW swap

nitec

Vendor
Joined
Jan 30, 2006
Location
Ottawa, ON
TDI
1.9TDi PD
Folks,

this has been a long time coming...The W8 base belonged to a long time TDiclub member - Fitzski...I've been on his case to sell me his W8 4Mo 6spd wagon for at least 3 years before he finally crumbled under the pressure. It then took me 2+ years of sorting out other projects before I found a suitable donor...long story short we started this project today and I`m really excited about it

The plan is fairly straight forward - complete BHW swap out of a B5.5 using all stock setup swapped into the B5.5 Wagon using the OEM O1E manual transmission - that's it. I'll build this for my mom or to sell so no Holset madness on this project

I've noticed there really isn't a good W8->TDi thread so hopefully this will help document the process a little better...

on with the pictures:

Here's the W8







Here's the extremely clean donor (short of a leaking valve cover gasket)



intercooler bracket needs to be moved over



this is where we stopped today



only things left to do before we pull it all out tomorrow are disconnect the driveshafts and the transmission shifter
 

nitec

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Location
Ottawa, ON
TDI
1.9TDi PD
BHW's out...



it's a chain drive BSM - I think the consensus is the leave it alone?



I've got a few gaskets to replace and then it's ready to be dropped in...the W8 is coming out next...

realized pretty quickly that the BHW AC will not work in the W8 so I`ll have to figure out a way to mount the W8 AC compressor to the BHW - perhaps using the BPW bracket from the Audi will work?
 

Windex

Top Post Dawg
Joined
Apr 1, 2006
Location
Cambridge
TDI
05 B5V 01E FRF
For the chain drive - the consensus is to delete it using an ALH pump.

What are you using for a clutch?
 

nitec

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Jan 30, 2006
Location
Ottawa, ON
TDI
1.9TDi PD
oh yeah? the BSM works fine for now - I`ll look up the procedure...it is just a matter of unbolting it and bolting up the ALH pump? there was some hole that needs to be plugged right?

clutch is likely going to be single mass Valeo kit...works great on my B7 so no reason not to use it...I was thinking of getting a dual mass but can't seem to find a reasonable kit for it...
 

nitec

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Jan 30, 2006
Location
Ottawa, ON
TDI
1.9TDi PD
is the BHW sprocket unusable? I've got the whole BRM assembly but don't feel like pulling the sprocket if I don't have to
 

Windex

Top Post Dawg
Joined
Apr 1, 2006
Location
Cambridge
TDI
05 B5V 01E FRF

otty

Veteran Member
Joined
Nov 7, 2010
Location
Revelstoke, BC
TDI
2003 Passat W8=>TDI swap, 4Motion Wagon, PD130(AVF) 6Speed Manual, 2006 Jetta MKIV PD(BEW) Wagon 5Speed Manual
Watching with interest! Still a few wiring issues with my swap but some may be different than yours given the AVF engine/ECU in mine.
 

nitec

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Jan 30, 2006
Location
Ottawa, ON
TDI
1.9TDi PD
hmmm...the engine is really clean so I was hesitant to get into big tear down exercises but I think this is worth doing...I've already got a few oil pumps kicking about so should be ok - will need a new sprocket though that's for sure...

My parts list is shaping up like this:

- front and rear crank seals
- oil pump sprocket
- BRM (or BEW or 1.8T oil pump)
- Valeo 228mm SMF clutch
- 1.8t pilot bearing
- valve cover and tandem pump gaskets
- oil filter housing gasket

that's about it...was thinking of taking the intake and turbo off to chance gaskets there too but again - everything looks new so I`ll leave it at that...

am I missing anything in the "while in there" category?
 

otty

Veteran Member
Joined
Nov 7, 2010
Location
Revelstoke, BC
TDI
2003 Passat W8=>TDI swap, 4Motion Wagon, PD130(AVF) 6Speed Manual, 2006 Jetta MKIV PD(BEW) Wagon 5Speed Manual
AC is not working currently. It is somehow not wired correctly and I haven't figured it out...
 

Mikkijayne

Veteran Member
Joined
Nov 10, 2007
Location
Devon, UK
TDI
Audi S8
realized pretty quickly that the BHW AC will not work in the W8
Can't you just swap everything under the hood from the BHW in to the W8 body - pipework, condenser, drier & compressor? The point where the lines enter the cabin is standard so as long as you swap everything it should all be fine surely?

The AC controller in Audis can be coded to either mag-clutch or internal valve so I would assume the Passat one is exactly the same if thats the issue?
 

TDIMeister

Phd of TDIClub Enthusiast, Moderator at Large
Joined
May 1, 1999
Location
Canada
TDI
TDI
Single mass flywheel clutches are documented to destroy 01E synchros in short order. Good luck with the build. Do something mad with the leftover W8 engine. A straight exhaust alone brings out the single plane V8 Ferrari-like sound. Search YouTube to see/hear what I mean.
 
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nitec

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yeah I read about the SMF 01E situation...not sure how I feel about it - my B7 uses the same style transmission and it runs like a charm with the 228mm SMF...I find it a little hard to believe the "strongest" Audi transmission that people use behind all of their high HP turbocharged motors with SMFs fails just because it's mounted to a diesel engine where an O1A apparently doesn't...I dunno - every other option costs twice as much so I'm pretty sure I'm going down that path anyways...I wonder how many O1Es/SMF sets have actually failed and how long each one took...

MJ - interesting...I wouldn't think you can do that with VCDS? I've got a few different brackets to try out over the next few days to see if I can get the W8 AC mounted to the BHW the same way I did it in the B7...there's no issue mounting it the same way that the BHW was mounted - the only problem is the clutch activation so if you think that can be adjusted then it may be pretty straight forward...

otty - do you have a pic of your AC setup? I suspect the previous owner kept the BHW setup, which doesn't work with the W8...perhaps MJ will help us with out with this
 
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nitec

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Ottawa, ON
TDI
1.9TDi PD
if the W8 goes FI and I agree that it should it will be one of these sitting on top of it



...I've got too many Holsets sitting in the basement to get a charger :) The problem with the W8 is there are NO performance parts for it...I'd have to get custom pistons to drop the compression...can't do much with it

Ideally I'd sell the engine because it's one of very few out there in a good condition but I've had it listed for a while now and it's not moving...if I had to "do" something with it I've got that B5 caged chassis just sitting there that the engine will swap in directly...the other option was the B4 Wagon if I pulled out the AAN engine out of it...both options would be insane :)

haha that B5 engine plan has changed 5 times now :) every time I get an engine made for it I use it for another car...if I ever get a motor in it it'll be a celebration
 
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vtpsd

Veteran Member
Joined
Aug 15, 2013
Location
Vermont
TDI
03 jsw TDI, audi 90 AHU swap
dude....I LOVE my SRE dual mass flywheel and clutch setup, and feel its worth every penny.....just sayin.

Frans had it for a good price.
 

Mikkijayne

Veteran Member
Joined
Nov 10, 2007
Location
Devon, UK
TDI
Audi S8
As suspected, the W8 uses a compressor with an internal regulating valve, the same as the V6 models. N280 in this diagram:



The BHW uses a magnetic clutch:



All you should need to do to make the W8 Climatronic unit drive the BHW compressor is add a relay and the wire to the clutch, and code it accordingly. I did this in my A6 2.5 > 1.9 swap and it worked perfectly.

The only challenge is that I can't find the coding tables for the Climatronic unit which is annoying. However, if you swap the unit from the BHW in to the W8 it will already be coded correctly for the mag clutch relay instead of the internal valve. I will keep looking for the coding table though.

The wiring diagram is laid out differently for both models, but I would be very confident they are identical apart from the compressor control. Thats certainly the case in the B5/C5. I'll upload the complete diagrams this evening for comparison.
 

nitec

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Ottawa, ON
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1.9TDi PD
thanks MJ - that's solid info to have...here's my little AC investigation today

BRM vs. W8 (pretty much the same)




BHW vs BRM (different ports and clutch vs. valve)



BPW bracket



W8 compressor mounted on the BPW bracket



the only thing I need to confirm is whether the W8 hoses will work with the AC compressor mounted on the BPW bracket...also this bracket requires me to change the pulleys on both the alternator and hydraulic pump to use the wider belt...I think we're in good shape
 

stp359

Veteran Member
Joined
Mar 24, 2014
Location
Montreal, QC
TDI
Passat 4motion tdi 6speed
I did this swap in an 04 Passat wagon V6 4motion. It was Automatic so I had to swap everything. I got the transmission from an Audi A6 2.5TDI 180hp which has the tallest possible gearing. It has the same final drive(3.89) as the W8 fron what I remember. PS: the A6 2.5TDI 150hp has the 4.11 final deive. With 120km/h (75mph) I was at around 2100rpm. About the A/C, it was plug and play as the V6 a/c compressor uses a clutch. I think the W8 works on a duty cycle. I just had to code te ECU for climatronic and it worked perfectly. In your case you will have to run some wires and code the Climatronic module for another engine. I could help with wiring diagrams if you need them and other stuff. About the clutch I first used a stock 1.8t 228mm DMF clutch that I had it was almost brand new. It lasted about 60 000 km before the flywheel gave up. The cluth itselft didn't have much left either. It couldn't take the torque. It would slip if I push it a bit harder, not all the time but it did slip. I went for a heavy SMF with a 240mm clutch. Thr difference I can tell from my own experience with both clutches tested in the same car is that you have to keep your RPM higher ( 1800rpm+) with the SMF. You can't cruise at 1300-1400 rpm. You will destroy the transmission. If you go with the SMF flywheel make sure you get a heavy one(at least 20lbs). The light one makes the vibration even worse as the tdi engine is a high compression engine. I also have thr same clutch set up in my Allroad with the BHW engine. I'm at 60 000km since the swap and no problem. I drive above 2000rpm all the time and no problem. I took it for a road trip around the world. I'm in Cancun, Mexico for now and didn't have a single problem with te tranny/clutch so far. We'll see further south.
 

stp359

Veteran Member
Joined
Mar 24, 2014
Location
Montreal, QC
TDI
Passat 4motion tdi 6speed
As suspected, the W8 uses a compressor with an internal regulating valve, the same as the V6 models. N280 in this diagram:



The BHW uses a magnetic clutch:



All you should need to do to make the W8 Climatronic unit drive the BHW compressor is add a relay and the wire to the clutch, and code it accordingly. I did this in my A6 2.5 > 1.9 swap and it worked perfectly.

The only challenge is that I can't find the coding tables for the Climatronic unit which is annoying. However, if you swap the unit from the BHW in to the W8 it will already be coded correctly for the mag clutch relay instead of the internal valve. I will keep looking for the coding table though.

The wiring diagram is laid out differently for both models, but I would be very confident they are identical apart from the compressor control. Thats certainly the case in the B5/C5. I'll upload the complete diagrams this evening for comparison.
Which engine did you use in the A6? I put a BHW in my Allroad and I have some problems with the a/c. There are 3 wires going into the ECU from the Climate control module. On the BHW they are only 2. As I saw on another post I connected 2 of them together(I could check which ones exactly) and the 3rd was for the RPM. The A/c was not working well. Sometimes it would freeze and not let any air go through or the compressor will keep turnin on and off. Also the vent flaps don't work properly. Now I have no a/c because one hose broke and I'm about to die. It's getting really hot in Cancun.
 

Mikkijayne

Veteran Member
Joined
Nov 10, 2007
Location
Devon, UK
TDI
Audi S8
I put an AFN in my A6 which was an option in the C5 from the factory, just not with Quattro. It worked first time, but I was using all the same generation stuff so it was pretty simple. All I had to do was code it for the clutch and add the relay & wire to the compressor. The connections from the AFN ecu to the AC were the same as for the original 2.5 ecu.
 

nitec

Vendor
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Jan 30, 2006
Location
Ottawa, ON
TDI
1.9TDi PD
hmm...if I used the BPW bracket then I'd keep the W8 fan setup so no issue with the power...in any case adding an extra fan is fairly simple

judging from this picture the stock W8 lines may need a little convincing to fit with the BPW bracket, which puts the compressor underneath...



 
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Windex

Top Post Dawg
Joined
Apr 1, 2006
Location
Cambridge
TDI
05 B5V 01E FRF
I didn't even realize that the W8 has the timing chains at the back a-la VR6, 2.5L etc.

If they're given quality oil at regular intervals do the timing chains last a decent amount of time?
 

stp359

Veteran Member
Joined
Mar 24, 2014
Location
Montreal, QC
TDI
Passat 4motion tdi 6speed
I put an AFN in my A6 which was an option in the C5 from the factory, just not with Quattro. It worked first time, but I was using all the same generation stuff so it was pretty simple. All I had to do was code it for the clutch and add the relay & wire to the compressor. The connections from the AFN ecu to the AC were the same as for the original 2.5 ecu.
From what i found the only engine with a clutch regulated a/c is the 2.7T/2.8
Do you remember how you did the wiring and what coding you used for the climate control module?
 

nitec

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Ottawa, ON
TDI
1.9TDi PD
I didn't even realize that the W8 has the timing chains at the back a-la VR6, 2.5L etc.

If they're given quality oil at regular intervals do the timing chains last a decent amount of time?
the W8 has a bad reputation because it's a complex beast and most people cut corners on the maintenance...this engine has been meticulously maintained and it shows...at 220k km or so it runs like new with zero issues...it is very hard to work on because of how tight it is but there are plenty of examples out there of other engines with the same issues - the 2.7T in a B5 comes to mind...
 
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