TDI/MTDI, Turbo choices? Biturbo maybe?

[TurboThimo]

Hello everyone!
This is my first post here so I assume I deserve to introduce myself first. My name is Thimo Koolhof, I live in the Netherlands close to the border of germany and I own 2 MK1's. Both MK1's will be going to be fully rebuild, one of them will be a MTDI and the other a gasser. Of course I will be talking about the Diesel only in this forum.

I have recently gotten my hands on a 1Z engine with all accesories on it and I plan on converting it to a MTDI. Let me type out the main plan down here...

For the pump I have 2 TD pumps from Germany to come in the mail soon, I planned on using the Hybrid pump (AKA Frankensteinpump) for now until I get my hands on an affordable Rover/LT pump. So this pump will consist of a TD housing with TDI camplate and pumphead swapped in. I hope to get my hands on an 11mm TDI pump soon also, as my 1Z pump has the 10mm head.

Now for the engine it will be rebuild in house and the head will get a port and polish job also. Then probably some head studs and a 3 hole metal gasket. I happen to got my hands on a (what I believe) 150PD intake manifold. Just preparing it to get the most out of it on the 11mm pump until getting the 12mm or larger pump ready.

My 1Z came stock with a KKK K03 turbo, I find it rather small and I am looking for a fairly affordable upgrade to make good overall power, as it will be dailied more then raced or anything. I only want wastegated turbo's, no VNT stuff for now. I have been looking into the GT2052 and HE200WG until I thought of something more interesting and I guess unique? Has anyone ever used a Biturbo on a TDI?

As my grandpa has a merc GLK, I wondered what turbo would be on that engine and it turned out to be a BorgWarner Biturbo, which I can get for a good price. The number is A6510902880. Now for the questions...

1. Would this turbo possibly work on a 1.9 with custom manifold?
2. How in the world can I manually control these 2 turbos and how much boost can they possibly take?
3. Where to get the stronger 12.9 main cap bolts, any part numbers or sites?
4. Any other tips and tricks that I should be aware of, as I am fairly new to this?

My thought of question 2 would be 2 seperate boost controllers and set each turbo wastegate to its own pressure. where to base the boost off of for the controllers tho?

All helpful tips and info is highly appreciated!

Kind regards,

Thimo Koolhof

[libbydiesel]

For the pump I have 2 TD pumps from Germany to come in the mail soon, I planned on using the Hybrid pump (AKA Frankensteinpump) for now until I get my hands on an affordable Rover/LT pump. So this pump will consist of a TD housing with TDI camplate and pumphead swapped in. I hope to get my hands on an 11mm TDI pump soon also, as my 1Z pump has the 10mm head.

That will probably run but will still be under-fueled.  The mechanical TDI control collar lever assemblies are offset to give more overall movement to the control collar.  That makes a fairly significant difference in fueling potential.

I think that doing a standalone VNT control would be a lot simpler than compound turbos.  Compound turbos would have quite a bit more overall potential but in order to take advantage of that you would need a better injection pump.  That sounds to me like a lot of work and, if you manage to get it dialed in, an end result which would be way more power than I would want in a Mk1.  If you do it, it would be fun to see pics.  A block girdle would be wise.   

[TurboThimo]

For the pump I have 2 TD pumps from Germany to come in the mail soon, I planned on using the Hybrid pump (AKA Frankensteinpump) for now until I get my hands on an affordable Rover/LT pump. So this pump will consist of a TD housing with TDI camplate and pumphead swapped in. I hope to get my hands on an 11mm TDI pump soon also, as my 1Z pump has the 10mm head.

That will probably run but will still be under-fueled.  The mechanical TDI control collar lever assemblies are offset to give more overall movement to the control collar.  That makes a fairly significant difference in fueling potential.

I think that doing a standalone VNT control would be a lot simpler than compound turbos.  Compound turbos would have quite a bit more overall potential but in order to take advantage of that you would need a better injection pump.  That sounds to me like a lot of work and, if you manage to get it dialed in, an end result which would be way more power than I would want in a Mk1.  If you do it, it would be fun to see pics.  A block girdle would be wise.   

Thanks for your fast reply and your information! I should have seen it comming that the hybrid pump just won't do the compound system any good... perhaps I can make a pump, rebuild the second and sel them again maybe. I should be able to buy either a Rover or LT pump, with a 12mm head, would that be enough or can you maybe recommend me another pump which has a bigger pump head, maybe a combination again?

Also, I took a closer look at the block tonight after further stripping down and noticed it was actually an AHU instead of the 1Z I was told it was. After a quick search on the forums I made up that it won't influence my plans, as it's just kind of a further developed version of the 1Z.

A block Girdle should not be a real problem to the budget as long as a gasser one fits?

I am defininitly interested to dive into this more and start gathering more parts. If only I would understand how to upload pictures in here, I could give some examples of the setup that I mean instead of just random part numbers. I will make a new post when the actual build of the engine and everything will start, I like doing things different.

[libbydiesel]

Land Rove pump would have decent fueling potential and an LT pump would have much higher fueling potential than what you proposed previously.  LR pump had an 11mm head, but a somewhat wimpy camplate.  LT had 12mm head.  Another option would be a Cummins 4BT but internal mods of timing advance and governor spring would be necessary.

Here's a thread on posting pics:  http://vwdiesel.net/forum/index.php/topic,13132.msg92927.html#msg92927

Block girdle for gasser should work fine assuming it is for the early block style.

I have seen compound turbos posted on this forum before.  IIRC Andy2 did compounds on an AAZ including custom head gasket and fire rings along with various other mods.  That was a while back.   

[TurboThimo]

I sadly will have trouble with finding a 4BT pump in europe, I am quite sure of that. How interchangeable are parts of the pumps, will internals and pump heads fit from different car brands as long as the pump itself is a Bosch unit? Then I could maybe combine a Rover pump with the LT pump, or a TDI pump with the LT pump? Or would that make no sense?

Thanks for the tip on the pictures, its clear to me now. I will look for a good free image hosting that also gives that link tomorrow. For now I will use the google service as long as that is not a problem?

Here are some pictures about the turbo's in question...
 https://photos.app.goo.gl/PUgY4ACXPQWLk9XAA