B4 turbo options

[thechoochlyman]

Who has installed a VNT in their B4? Looks like it would be quite an undertaking considering the intake, exhaust, and charge pipes are all different. I'd like to go with an 1856v or at least a 1752.

 

[JordanTr]

There are lots who have done it. I have gathered some parts but haven't taken the plunge yet. I purchased a GTC1549VZ which will need the adapter plate to fit the manifold and a new downpipe. Depending on the turbo chosen, you may or may not have turbo inlet/engine mount interference. An AFN/BHW manifold helps to alleviate that somewhat by aiming the turbo more toward the firewall than the original 1Z/AHU mani.

John Jackson's car with the 1549 turbo posted pretty impressive results for a relatively stock 1Z.

Here are some threads to peek at:

The Garrett GT2052 aka "Look Ma, No Vanes!"

I recently upgraded the turbocharger on my 91 GTI. I had conferred with Mr.Chill about a good turbo upgrade suggestion and he told me about driving a mk2 Jetta Coupe with an AHU and a GT2052 and that it was an absolute blast to drive. That was last fall/winter IIRC. Needless to say, after a lot...

forums.tdiclub.com

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...

forums.tdiclub.com

Beater Build: vnt15 1z

I figured I should post a thread on the current car I'm building. 1997 Passat w/208k miles (and some residual damage from a WI deer) and a dead hole. Game plan: 1) remove drivetrain from car (head already removed) 2) swap in a used shortblock (194k AHU - Thanks Kirk!) 3) install...

forums.tdiclub.com

FS: VNT conversion for B4/A3 AHU/1Z

For sale VNT conversion kit (used) for B4/A3 AHU/1Z with wastegate turbo. Parts included: AFN exhaust manifold AFN turbo inlet pipe AFN intercooler pipe AFN oil feed + return line AFN downpipe flange AFN N75 valve with bracket and vacuum line Manifold and downpipe gasket (new) With...

forums.tdiclub.com

vnt and 1z

Guys what will happen if I don't get the n75 or ecu reprogrammed. Also I have a gq do I just need tuned chips or i need another chip soldered in there?

forums.tdiclub.com

help with turbo choose for my 1z?

Hi guys. I got a 1z 90hp from a 1996 passat That im gonna transplant it to my volvo 745 station vagon, and my turbo have seen greater days, its time to change it, so better just to do a upgrade. What turbos are there that would work great for my 1z, making good power and still be good fuel...

forums.tdiclub.com

Exhaust manifold: AHU/1Z vs. AFN

Hey all I did a cursory search on the forum to see if something existed but I couldn't find anything about this. Looking at upgrades for the new project and would like to switch to VNT without having the fitment problems with the right rear engine mount and the Mk4 VNT setup so I'm wanting to...

forums.tdiclub.com

Keep us posted what you figure out!

 

[burpod]

definitely wouldn't get anything smaller than a "1752". if i were to do things over again, i would get at least a newer gen turbo like maybe a gtb 2056 or gtd2060vz for example (check powertdi or muchboost), since you're going to have to change the downpipe flange and boost pipes/connections anyway. imo, the best compressor outlet (at least for an mk3) would be a straight barb outlet and take the boost pipe up over the valver cover to an fmic. (which is what i've done). not positive if these turbos actually fit an mk3/b4 with the motor mount issue, but i know 1752/1856v will fit with the aftermarket motor mount bracket. i plan on trying a gtd 2060vz next time i have money. just only 99% sure it will fit... not 100%

if you want to run boost of a "1752" say 25-26psi average max, you're really going to want an fmic or at least somehow a very well cooling smic - at least if you want to use that power when it's warm out.

 

[thechoochlyman]

I just pulled the trigger on an AFN exhaust manifold - seems like it'll make things go easier without having to modify the engine mount.

Now I'm getting really lost in the weeds with all of Garrett's crazy numbers and letters. Apparently the GT1749V is smaller than the GT1749VA GT1749VB, all of which correspond with the PD100, PD130, and PD150 respectively. I put out a feeler in the buy and sell forum for a used GT156V or BV43, but I only know for sure the latter of which should bolt up to an AFN manifold (at least, the one that Cascade German sells).

Ugh. I just want something relatively inexpensive to buy used that will perform a ton better than my GT15 - which I feel like is pretty much anything else. What do you think, Guthrie?

 

[burpod]

I just pulled the trigger on an AFN exhaust manifold - seems like it'll make things go easier without having to modify the engine mount.

Now I'm getting really lost in the weeds with all of Garrett's crazy numbers and letters. Apparently the GT1749V is smaller than the GT1749VA GT1749VB, all of which correspond with the PD100, PD130, and PD150 respectively. I put out a feeler in the buy and sell forum for a used GT156V or BV43, but I only know for sure the latter of which should bolt up to an AFN manifold (at least, the one that Cascade German sells).

Ugh. I just want something relatively inexpensive to buy used that will perform a ton better than my GT15 - which I feel like is pretty much anything else. What do you think, Guthrie?

if it were me, i would do the modified motor mount bracket and get a GTD - powertdi will make one that will fit, with GTD welded onto whatever manifold he uses for that. i previously orderd a gtd2060vz thinking it might fit "as is" but with compressor outlet welded more straight-out like a vnt15, but unfortunately it didn't come close to fitting even with the aftermarket motor mount. but then i talked to him and he said they will make any of their turbos fit if you specify which chassis... so i'll be saving this 2060 i have for another car, and i ordered another, this time specifically saying for my mk3. hopefully should have it in a week or two and will take pics and test fit it.

you could ask @garciapiano about his bv39 he's running. as well as @irishjetta - also with bv39 - both running 11mm .260s and a certain tune

the vnt17 is only a pretty small upgrade from a vnt15, the excitement of the top end power of that fades fairly quickly.... the bv39 seems me is borg warners equivalent of the the vnt17. it performs great from what i've seen, just still pretty limited in boost.

if i were to do a GT turbo, i'd simply just get the aftermarket motor mount also + a gt1856 from xman/powertdi. i'd rather change the motor mount out and have known fitment rather than messing with other manifolds which i myself have never tried...

 

[thechoochlyman]

There's a seller on eBay called "Worldwide Turbo and Injection" located in Florida who sells direct from Garrett. They have a four-bolt GT2056 on their store page for $500, and mentioned that they're able to assemble pretty much whatever you're looking for. I sent them a message and asked if they could quote a wastegated GT1856V with a three-bolt exhaust housing and straight angle compressor housing. Never hurts to see what they come up with, right?

 

[garciapiano]

I'm happy with my BV39 setup on my Mk3. It is more than fast enough for the kinds of driving I do. It always surprises my passengers when they get thrown back into their seats.

Mk3 Jetta Engine Bay

• garciapiano
• Jun 9, 2024

BV39, 11mm Pump

Because this car is my daily driver, I went fairly OEM+ with my turbo swap on my mk3 to keep things straightforward:

• Stock, rebuilt 1Z
• BV39
• 11mm Pump
• .260 Nozzles (Burpod group buy)
• AFN manifold
• PD130 intake
• Off the shelf aftermarket AFN style catted downpipe from Europe, stock Mk3 catback
• Braided feed line from 98JettaBioDiesel, and the drain line from a later Passat PN# 028145736AH
• Kept stock intercooler piping and intercooler, for the most part, needed a couple of misc silicone hoses, reducers and clamps to make it all work
• I could not find an off the shelf turbo support bracket that would actually fit and not interfere with the drain line, so I had to cobble together some different OEM pieces to make one.

As it sits right now, the car rips, with very little smoke in daily driving. Butt dyno says maybe 150-160 HP conservatively. Still working on a MPG figure but I think I'm better than stock MPG, even with 205/50R15 tires on the car.

But, there are some caveats and compromises with this setup. The BV39 turbo has a clip-style outlet so it needs an outlet adaptor, which adds costs and introduces a failure point. None of the outlet adaptors I could find on the market fit that specific turbo out of the box without leaking, which sucks. I had to get the one from Cascade German and dremel the lip down a couple millimeters to get it to clip into the turbo securely. It does not appear to leak now.

The turbo support bracket is an issue, curious to see how other people have managed to find one that fits out of the box.

You can put the integrated manifold style turbos on the Mk3/B4, you just need a modified rear motor mount bracket (darkside developments sells one) and probably a custom downpipe. The integrated manifolds definitely flow better, that's why they went to them.

Unfortunately, the cold side on those newer turbos off the shelf usually don't route nicely for the B4/Mk3 engine bay so you need something custom-made for the application. To use the stock piping on the Mk3/B4 you want one that shoots straight up and over the exhaust manifold, or ideally up diagonally towards the trans (not too many modern TDI turbos are routed this way due to the newer cars having the airbox on the driver side).

If I were to do it again I'd just get a bigger, newer turbo with a billet compressor wheel. Or what Burpod said... GTD20XX-series style turbo with the compressor housing modified to work with the Mk3 routing. That said, I think I am close to the theoretical flow limit for power on this car without needing to start getting fancy with internal work, high lift cams, pistons, oil cooling, intercooling etc. so a bigger turbo might be overkill for this engine.

It really starts to snowball fast with the power game and I mostly want a setup that is a good balance of power, daily-ability and reliability. I think this accomplishes that. Probably the only thing I would change on this setup is a more free-flowing 2.5" exhaust and a front mount intercooler, but again... I'm getting lazy... End of the day, I also just don't think the 1Z head flows as well as later cars... and its top end potential is somewhat limited by the older block design and I really don't want to push it.

I'm really happy with this car, and Burpod has done a great job of tuning it. Just wish I could flash tune instead of chip tune! Going to EDC15 ALH management will probably be in the cards at some point... Just need a guru to help me out with the wiring.

Oh, and don't bother with a wastegate turbo if you're going to the distance. There's a reason we went away from those too.

 

[thechoochlyman]

Great info there, thanks! Looks like the BV39 was stock on a BRM?

 

[garciapiano]

Great info there, thanks! Looks like the BV39 was stock on a BRM?

Was stock on BHW, I believe. Could be on others. It is the Borg Warner equivalent of a GT1749VA. It was the stock turbo on PD130s in Europe.

 

[thechoochlyman]

Was stock on BHW, I believe. Could be on others. It is the Borg Warner equivalent of a GT1749VA. It was the stock turbo on PD130s in Europe.

Ah, makes sense. Throwing in all the Borg Warner turbo models makes it seem more complicated, but it's basically the equivalent of the K03 vs GT15.

I just now came across an old thread giving cross reference numbers for the BV43 and managed to find a reman unit in Germany for a good price, so I pulled the trigger on it. Now the deciding is finally over and I can move on to the test-fit stage when it arrives.

 

[thechoochlyman]

Well, you can scratch my previous statement - apparently the eBay seller wants an additional core fee paid via PayPal, so I'm not doing that.

@garciapiano, I think I'm going to follow in your footsteps and go with the BV39 too. I'm sure I can machine something to clip into the compressor outlet. I also like the idea that is should be relatively easy to find, considering it was stock on the B5.5 TDI.

 

[garciapiano]

Yeah, it's like a $250 turbo used from a lot of yards. I found mind brand new from Germany on Fleabay for around $500 IIRC

 

[thechoochlyman]

AFN manifold showed up from Europe today. Also have a GT1749VA coming from a guy in Canada.

 

[thechoochlyman]

Turbo came in this week. Getting closer to starting a real swap. Need to reclock the compressor housing and apparently completely redo the exhaust flange angle. lol

 

[thechoochlyman]

Starting to test fit everything on my spare engine. I think the oil feed line I bought is wrong. Maybe I can have Napa splice pieces together with hydraulic line.

 

[thechoochlyman]

Figured out part of my problem is that the oil feed adapter is missing on the turbo. Measurements are M10x1.0 turbo side and M14x1.5 line side. The VW part is like $150 from most retailers, so off to eBay I went. Found this one for $20 shipped from Latvia. PN 28145786

 

[burpod]

you could also get a couple metric/an adapters ($5 each) and a $20 3 4an stainless braided line

 

[thechoochlyman]

I kinda want to keep a hard line on the oil feed if possible, not dead set on it though. I'm honestly more concerned about how to rig the drain line. lol

 

[garciapiano]

Theoretically the AFN feed line works. But I used a stainless line from 98jettabiodiesel and it’s been fine. He uses a banjo fitting to kick the oil line out the right way from the filter bracket.

I used a BHW drain line.

 

[Steve Addy]

AFN manifold showed up from Europe today. Also have a GT1749VA coming from a guy in Canada.

View attachment 138472

That's the same manifold as the BHW except that BHW has a probe port already drilled and tapped, no need to go to Europe for that.

Steve

 

[thechoochlyman]

028145771BE Oil feed tube came in over the weekend and fits perfectly.

 

[thechoochlyman]

Did a little whittling today. The turbo inlet adapter I make is for the K03, and the BV39 has the same bolt pattern. However, the inlet is about .010" larger. That's just enough to make my adapter super tight, so I took .010" off the diameter.





And I made myself an outlet adapter for use on the stock pipe.

 

[JordanTr]

Is the inlet pipe bolt pattern clocked the same way to the compressor outlet on both the VNT17 and the old GT15? Very handy if that’s the case!

 

[thechoochlyman]

Is the inlet pipe bolt pattern clocked the same way to the compressor outlet on both the VNT17 and the old GT15? Very handy if that’s the case!

Well, the same inlet pipe would bolt onto it - but I'm sure it won't be clocked in the right position relative to the engine and accordion hose. Luckily I have another inlet pipe that has broken ears, so I'll be able to bolt everything up to my parts engine and epoxy it onto my flange at the right angle to meet the accordion hose. At least, that's what I'm planning on. haha

 

[garciapiano]

All the “VNT17” compressor outlet adaptors on the market don’t seem to fit or fit poorly to where they leak boost. It would be amazing if you could start making those. @thechoochlyman

 

[JordanTr]

I was thinking of cutting a welding a barb on my VNT17 to eliminate any leaking o ring etc opportunities. I also have a TIG but no lathe!

 

[thechoochlyman]

All the “VNT17” compressor outlet adaptors on the market don’t seem to fit or fit poorly to where they leak boost. It would be amazing if you could start making those. @thechoochlyman

Not gonna lie, I did consider it but it seems like there are a lot of options already out there. What about the ones from ECS tuning? I could probably try to make them for around $80-$100.

I didn't put the little ears on mine to hold it in the turbo, I drilled and tapped a couple of blind 3mm holes to bolt it in where the clip usually goes. It's a great fit, though - I can shove it to the bottom by hand but have to grab it with the lathe chuck to get good enough of a grip to pull it loose.

 

[garciapiano]

That's a neat design.

I'm not sure how strong that little M3 bolt is in shear, though.

They all appear to be similar in concept but there appear to be slightly different fitments by turbos. Especially confusing because there are multiple turbos referred to as "VNT-17s".

Like Borg-Warners appear to have an ever-so-slightly different "clip in" depth than the Garretts? Which doesn't make sense.

For example I bought a "VNT-17" adaptor from TDI-Upgrades and the outside diameter was all wrong, didn't fit close enough to the housing.

Then I bought another one from Cascade German but it did not fit my BV39 properly without grinding down the collar that sits on the outside edge of the housing.

It wouldn't engage the clips all the way otherwise. I literally have the OEM BHW turbo so I'm not sure why it didn't fit.

Anyway... a little R&D on your part would help us all out!

 

[burpod]

All the “VNT17” compressor outlet adaptors on the market don’t seem to fit or fit poorly to where they leak boost. It would be amazing if you could start making those. @thechoochlyman

yup. seen many of those leak. boost leaks drive me nuts with tuning.. eveyrone swears they don't have any... until they actually look at every connection very closely or pressure test

 

[thechoochlyman]

That's a neat design.

I'm not sure how strong that little M3 bolt is in shear, though.

I'm not too concerned about it... I'm sure it'll be blowing boots off before those bolts snap. lol