5 cylinder tdi ve turbo upgrade/compunds

Hi all,i am new to site looking for some advice please.
Winter is coming and more spare time i got so time to play.
I have on the engine stand 2.5tdi engine,5 cylinder,bosch ve pump,11 mm pump head standard bosch 0.216 nozzles.
And i do have some spare turbos, so i am thinking why not try making compound set up.
I have on the shelf brand new garrett gt2052s turbine a/r 0.50 waistgated from perkins phaser 4ltr engine, nice turbo,some one on this forum fitted it to 1.9 tdi with grate results as single.
Then i do have new holset hy35w 10cm housing single scroll from a bus with Cummins engine.
I do have tdo4 with 6cm,needs new chra and also have garrett gt2259s waistgated from iveco 4 litre diesel engine turbine ar0.56.
No what i am thinking,pair up gt2052s as high pressures
And used hy35w as low pressure?? And used egr port on exhaust manifold for external waistgate too.
Gt2259s might be to big for high pressure one?
Or do i use stock k14 fitted to 5 cylinder ael engine,old design turbocharger,waistgated with old fashion gate used on 80s mercs,vw,
If it would work and i can fabricated pipes etc and get it running on the floor then when time permits fit it all to the car i got with same engine?
I am hopping for more boost and volume of air and better spool up.
Any help and advice please
I got engine/turbos so hopping to make use of it all.
I got fair good access to turbos but unfortunately only from big diesel engines,Perkins,Cummins,Volvo etc.
Thank you.

2052 as the HP will give you the most stock-like transient response when you're off the loud-pedal. I would not twin anything on the HP stage because of the odd number of cylinders branching into two. It's not to say that you cannot do it, but I think 2X 2052s would be rather big. If anything, you would twin the LP stage instead of HP.

Of the turbos you have at your disposal, HY35W is the best choice as LP. Use the stock external wastegate (might have to adjust spring tension by trying different springs and shims) mounted to the exhaust manifold as sort of bypass around the HP and plumb it back upstream of the LP turbine inlet. The HP bypass can use exhaust manifold and inter-stage differential pressure as the control parameter.

Not sure whether the HY35W has an internal wastegate but if not, an external will be necessary so that you don't build-up dangerous boost pressures because of the compounding effect of a series connection of turbos. Let the ECU control boost with the LP wastegate (though you probably have an ancient MSA 8 or MSA 11 that's just not very capable...).

Some reading on series turbocharging:
http://bit.ly/2I6Kuyb
http://bit.ly/2PVZrFJ

Thank you so much for your replay and advice.

I dont think i made it clear in my post,sorry

As hp turbo i can keep stock k14 with its daft waistgate and use holset hy35w waistgated as hp turbo.
Garrett gt2052s is newer design and more efficient turbo so plan was to put it on as HP unit.
Both turbos HP and low pressure have internal waistgates then egr port will be used with external waistgate to baypass gasses in to hp turbo inlet to lower manifold backpressure.
But if k14 and gt2052s are simular it would be easier for me to work around k14 as its already in correct place angle etc.
I dont know gow to post photos but hy35 looks massive compared to gt2052s i had them side by side tonight.

At the moment it dosent cost me any silly money having a go at it as turbos were peanuts from work, only need pipe material for now.
I would like to build somthing that spools bit better than stock but has more go over 3.7k rpm.
Thank you again

HP needs external WG so you can run pressures on both sides of diaphragm

of the choices, I'd go with the k14 and hy35

I don't know how well the k14 would hold up, but I've run a gt1752s as an HP for a while and the thrust bearing died in about 15k miles, despite being of the upgraded (GT22?) size. Radial bearings were fine, just the axial thrust bearing was eaten on the expected turbine facing side.

Dragonlfc said:

At the moment it dosent cost me any silly money having a go at it as turbos were peanuts from work, only need pipe material for now.
I would like to build somthing that spools bit better than stock but has more go over 3.7k rpm.

Click to expand...

heh, a man after my own heart

yeah, weld the internal gate on the k14 shut and use an external

Any compound setup will actually spool a little later than the HP as a single would, as you're also breathing through the restriction of the LP turbo trying to spool up the HP.

You could go with something smaller for the HP, like your GT2052, but the durability just isn't there in my experience. The TD04 might be a better choice for the HP if you want quicker spool than the k14. Unless it is actually a TD04h, td04l, or td04HL, in which case the turbine is similar size or larger than the k14.

Hi thank you

Td04 turbos i can find are from saab 2.0turbo petrol
Or from volvo turbos i think smallest saab is 5cm or even 6 cm,volvos are 6 and 7cm,both are hl turbos to my knowledge.
There is td04H with 4cm housing from Mitsubishi pajero/montero but they have triangle,diamond shape inlet.
Stock audi exhaust manifold is t2.
On other hand only place to fit extrenal waistgate is into egr port,port opening is 27mm,there is enough material to open it up to 30 mm on use pipe from there to waistgate,would 30mm opening be enough to let gasses out.?
Do you know of any other small frame turbos good for HP unit?
Holset he200w would be nice bit it costs fair amount.
Unfortunately we dont get at work any he200w or 25s
Smallest that comes is is 27w from small trucks.
Thanks again