UrS4 2.2T Avant project

[Thuppu]

No, stock Motronic with a RS4 MAF.

[Jamo]

Any more details on the turbo, expected spool and boost levels. Are you installing it with that exhaust housing with divided scroll?

[prj]

Said turbo can run upto 43psi boost on these engines, and has made close to 600whp.
This is of course with meth injection etc etc etc.

This is a GT35R sized turbo...

Thuppu, you will start breaking drivetrain stuff with this thing, especially if you launch the car...
Divided housing will be just fine, it will give no benefit, but also I don't think it will choke anything either.

Looks like someone is ready for "man boost"

[Thuppu]

It's a standard HX40 Super. 60/65mm with a #16 turbine housing. Hope to get full boost under 5000rpm's. Like prj told, this turbo like high boost, optimal is about 2,2-2,6 bar, but can easily do up to 3 bar. Here is one dyno plot with exactly same size Holset but Schrick cams.

[prj]

Only thing is, to make so much boost you will need octane boosting...
Was your compression ratio dropped?

I could not run much more than 2 bar flat on stock CR engine with a 30R, started losing power.
Of course this turbo has bigger hotside, so hopefully can run more boost.

[Thuppu]

Stock CR. I can also use a #18 housing but it maybe cost some spool. There is a few other issues also left, one is that the stock wastegate can be too restrictive... maybe..? Second is how to fit the air-intake, MAF and filter. There is not too much space...

[Jamo]

Hope you have some spare driveshafts! super hx40 i've heard can shift some air, not my cup of tea but i've seen decent results out there on them in google

[prj]

Housing is perfect as is for your car. PM-d you.

[quattro84]

Awesome, very interested to see the outcome. Where did you get the 40Super? KKD?
@ prj: PM interesting enough to share?

[prj]

PM pretty much says:
"Call me, I have too much to say to type it all out."
I am afraid that's not helping

We will see how the car likes the 40 Super on the stock CR engine. I currently don't have too high hopes, I got crazy knock over 29psi on a 30R with a 0.82A/R housing, so I don't see how this will be much different.
I guess we can rev this engine further, so we will make more power than on a 30R, but torque is probably pretty much limited to 650nm or so.

[Thuppu]

2 bar could be just enough..? Did the 30R car has stock head? 7A cams if I remember right?

I don't want to have 700Nm on 4000rpm's, it's too much for the clutch(well, it should hold for 720+Nm). 650Nm on higher rpm's is just fine. I already have one torque monster so less is better on this one, but true power we want. I know a guy who use 7800rpm limiter with 7A cams and stock springs without problems, so maybe we can rev up to 8000..?

[prj]

8000 revs is not considered safe without improved oil pump and perhaps altered oil passages for 3rd cyl.
I would keep it to 7500-7600 on standard oil pump.

[prj]

30R has stock head, stock cams.

[Thuppu]

Ok, I have 7A exhaust cam and a cut AAN ex-cam as intake cam(+stiffer valve springs). The head is lighly ported, seats and valves re-shaped...

[A80Avant]

I have briefly used a holset HX40 with a bullseye .70AR hotside. Beautifull turbo for lag lovers. If you are looking at full boost at 5000rpm on (which gear?), i had 1.8bar on 3d @ 4700rpm, so since i have no idea what the twin scroll 16cm compares to the T3 0.70ar of the bullseye, i cannot comment.

For me, this turbo does indeed need more than 2bar to show it's teeth, but below that i must say, my 30R feels much stronger. Not only because it starts pushing earlier(much eariler), but also with a large hotside, it felt no different than the holset after 5000rpm. Unfortunately i dont have many logs to back that up, but i did do some runs with the holset with the Perfomance box which showed that indeed it doesnt do much below 2bar.

You will probably like it if you excpect full boost at the 5000rpm area.