Hybrid Rs2 Turbo

[S2central.net]

what are you tweaking & mapping it with out of interest ?

[prj]

By way of comparison... looking at some recent boost logs from an RS2 turbo'd S2 running V-stream and Wagner IC, customised for 0.8bar WG spring and spooling aggressively as it can...

In a 4th gear pull starting ~1850rpm
it goes positive boost before 1900
its making 0.4bar at 2400
0.8bar at 2750
and hits max target of 1.8bar before 3300... not aimed for 1.9bar on it yet but it shouldnt struggle to make that

Better to test in third... no comparison data in foruth...

It can approach 400bhp when running with injectors larger than RS2 as well.

Stock RS2 turbo won't get to that. Wishful thinking sadly.
Neither the turbine nor compressor flow enough. After you get to about 370 you start hitting a brick wall with this turbo. BTDT many times.

[david]

what are you tweaking & mapping it with out of interest ?

not mapping stage yet Paul.
that will be just changing compressor will with lighter one just to aid faster spool up.at the moment i'm using the old k27 wheel with flat back just like the k24 7000.
i believe with newer lighter compressor wheel with superback this will spool much faster.

[Ross]

If i remember correctly, Sal hit 400hp on his RS2 turbo, but it took some doing. Like 2.2bar and on it's way out by the redline... i would be interested to know how 3rd gear compares Paul / David, all mydata is for 3rd, I'm aiming for a hybrid similar to PRJ fitted before his engine expired, 410-420hp and 1.9bar in 3rd around 3800rpm.

@David, what power are you expecting to make and what are the details of this superback comp wheel? that's been the big undecided on my turbo, what comp wheel is best...

[S2central.net]

will see if I can get 3rd gear data on that one... its not fully optimised yet but blowing the right way

[david]

If i remember correctly, Sal hit 400hp on his RS2 turbo, but it took some doing. Like 2.2bar and on it's way out by the redline... i would be interested to know how 3rd gear compares Paul / David, all mydata is for 3rd, I'm aiming for a hybrid similar to PRJ fitted before his engine expired, 410-420hp and 1.9bar in 3rd around 3800rpm.

@David, what power are you expecting to make and what are the details of this superback comp wheel? that's been the big undecided on my turbo, what comp wheel is best...

Ross,
the hybrid i'm building will easly exceed 420bhp with little or no mapping.

with light superback compressor wheel,i have choice's of two really.one with 6 blades 78mm inducer 56mm exducer,and the other 81mm inducer 59 exducer with 7 blades.

always best to use the lightest wheel possible.

[Jamo]

If i remember correctly, Sal hit 400hp on his RS2 turbo, but it took some doing. Like 2.2bar and on it's way out by the redline... i would be interested to know how 3rd gear compares Paul / David, all mydata is for 3rd, I'm aiming for a hybrid similar to PRJ fitted before his engine expired, 410-420hp and 1.9bar in 3rd around 3800rpm.

@David, what power are you expecting to make and what are the details of this superback comp wheel? that's been the big undecided on my turbo, what comp wheel is best...

So did SteveH

[Zoig]

Thats not to pour cold water on the purpose of this thread in experimenting with other/older turbo - its just to remind everyone that turbo choice is a series of compromises... you cannot have one that spools instantly and has headroom for 1000bhp.

Any experiences with Holset HE351VGT? Should be possible to get fast spool and good top end with this geometry.

http://www.turbotalk.org/bb/viewtopic.php?f=25&t=174

Wheel dimensions.
Turbine
EX 2.357 ~60mm
IND 2.755 ~70mm

Compressor
EX 3.38 ~85-86mm
IND 2.37 ~60mm

[Ross]

David, are you making this kinda power from a stock RS2 hotside? Or have you changed the turbine? I thought the RS2 used a #6 hotside, and unmodified this limited to about 400hp... but the later spool suggests to me that you're a #8 or a bigger turbine wheel?

[Mcstiff]

Any experiences with Holset HE351VGT? Should be possible to get fast spool and good top end with this geometry.

http://www.turbotalk.org/bb/viewtopic.php?f=25&t=174

Wheel dimensions.
Turbine
EX 2.357 ~60mm
IND 2.755 ~70mm

Compressor
EX 3.38 ~85-86mm
IND 2.37 ~60mm

The downside of the HE341ve is that it is MASSIVE!

I think something like a HE341CW would allow for fast spool and >= 350whp.


Sent from my iPhone using Tapatalk

[prj]

If i remember correctly, Sal hit 400hp on his RS2 turbo, but it took some doing. Like 2.2bar and on it's way out by the redline...

As long as physics exist, this is not true.

Ross,
the hybrid i'm building will easly exceed 420bhp with little or no mapping.

Oh, so now hardware without mapping makes power by itself just lying there?
420 hp is not that super easy as you put it, 420hp with a K26/K27 hybrid on stock engine without some sort of chemical charge cooling is not doable either.

Ever wondered how people throw around hugely inflated hp numbers someones mothers sister did somewhere while going backwards and then that translates into unfounded expectations?

Sorry, don't mean to offend anyone.

[djh]

wonder how long stock rods will last on a modded unmapped turbo?

[david]

David, are you making this kinda power from a stock RS2 hotside? Or have you changed the turbine? I thought the RS2 used a #6 hotside, and unmodified this limited to about 400hp... but the later spool suggests to me that you're a #8 or a bigger turbine wheel?

yes mate,
i'm using stock rs2 hotside and bearing housing mated to k27 coldside,hence why i call it rs2 k27 hybrid.

[prj]

Well you can have a betting game of what lets go first - the rods or the bearings

Also RS2 turbine assembly does not really flow past 380hp. You just get crazy pre-turbo EGT and knock.

[djh]

Well you can have a betting game of what lets go first - the rods or the bearings

fairplay to david for trying new stuff tho. David have you got anything to monitor the engine or just vagcom?

and I'm gonna go for rod number 3 lol.